Read the following passage and questions, then choose the right answer from options, the answer should be one of A, B, C, D.

<passage>:
Extensive research did not uncover any evidence that the U.S. copyright on this publication was renewed.] The rider was of medium size, with huge, strong hands and seemingly from the river in the battered coffee-pot he had salvaged, and while he waited for it to boil, he went to his horse, Conqueror, stroking his slope where he hobbled him and left him for the night. all else was at rest. Images began to appear, drawn from inexhaustible files, wherein are kept all thoughts, past, present, and future.... It was the night before he was to go overseas. World War III had been declared, and he had enlisted, receiving his old rank of captain. He was with his wife in the living room of their home. They had put the children to bed—their sons—and now sat on the couch, watching the unexplored, some vastly different emotion he could never quite explain. sodden ground, and the air was heavy in his lungs. He had driven off in the jeep the army had sent for him, watching her there on the porch until the mist swirled around her feet and she ran back into the house little bulge under his uniform, and the touch of it seemed to warm the blood in his veins. Three days later they had landed in Spain, merged with another Three years later they were on the road to Moscow. Over a thousand miles lay behind, a dead man on every foot of those miles. Yet victory was near. The Russians had not yet used the H-bomb the threat of annihilation by the retaliation forces had been too great. He had done well in the war, and had been decorated many times for bravery in action. Now he felt the victory that seemed to be in the soldier needed to make him fight harder and live longer. Suddenly he had become aware of a droning, wooshing sound above him. It grew louder and louder until he knew what it was. "Heavy bombers!" The alarm had sounded, and the men had headed for their foxholes. But the planes had passed over, the sun glinting on their bellies, reflecting a blinding light. They were bound for bigger, more important targets. When the all-clear had sounded, the men clambered from their shelters. An icy wind swept the field, bringing with it clouds which covered the sun. A strange fear had gripped him then.... Across the Atlantic, over the pole, via Alaska, the great bombers flew. In cities, great and small, the air raid sirens sounded, high screaming noises which had jarred the people from sleep in time to die. The defending planes roared into the sky to intercept the on-rushing bombers. The horrendous battle split the universe. Many bombers fell, victims of fanatical suicide planes, or of missiles that streaked across the sky which none could escape. But too many bombers got through, dropping their deadly cargo upon the helpless cities. And not all the prayers or entreaties to any God had stopped their carnage. First there had been the red flashes that melted buildings into molten streams, and then the great triple-mushroom cloud filled with the poisonous gases that the wind swept away to other cities, where men had not died quickly and mercifully, but had rotted away, leaving shreds of putrid flesh behind to mark the places where they had crawled. The retaliatory forces had roared away to bomb the Russian cities. Few, if any, had returned. Too much blood and life were on their hands. Those who had remained alive had found a resting place on the crown of some distant mountain. Others had preferred the silent peaceful merciful beams of filtered light found their aluminum coffins. The war had ended. To no avail. Neither side had won. Most of the cities and the majority of the population of both countries had been destroyed. Even their governments had vanished, leaving a silent nothingness. The armies that remained were without leaders, without sources of supplies, save what they could forage and beg from an unfriendly people. They were alone now, a group of tired, battered men, for whom life held nothing. Their families had long since died, their bodies turned to dust, their spirits fled on the winds to a new world. Yet these remnants of an army must return—or at least try. Their exodus was just beginning. Somehow he had managed to hold together the few men left from his force. He had always nourished the hope that she might still be alive. And now that the war was over he had to return—had to know whether she was still waiting for him. They had started the long trek. Throughout Europe anarchy reigned. He and his men were alone. All they could do now was fight. Finally they After months of storms and bad luck, they had been shipwrecked somewhere off the coast of Mexico. He had managed to swim ashore, and had been found by a fisherman's family. Many months he had spent swimming and fishing, recovering his strength, inquiring about the United States. The Mexicans had spoken with fear of the land across the Rio Grande. All its great cities had been destroyed, and those that had been only partially destroyed were devoid of people. The land across the Rio Grande had become a land of shadows. The winds were poisoned, and the few people who might have survived, were crazed and maimed by the blasts. Few men had dared cross the Rio Grande into "El Mundo gris de Noviembre"—the November world. Those who had, had never returned. In time he had traveled north until he reached the Rio Grande. He had waded into the muddy waters and somehow landed on the American side. In the November world. It was rightly called. The deserts were long. All plant life had died, leaving to those once great fertile stretches, nothing but the sad, temporal beauty that comes with death. No people had he seen. Only the ruins of what had once been their cities. He had walked through them, and all that he had seen were the small mutant rodents, and all that he had heard was the occasional swish of the wind as it whisked along what might have been dead leaves, but wasn't. exhausted. The mountains were just beginning, and he hoped to find food there. He had not found food, but his luck had been with him. He had found a horse. Not a normal horse, but a mutation. It was almost twice as large as a regular horse. Its skin seemed to shimmer and was like straight out, as the horn of a unicorn. But most startling of all were And he had followed. Over a mountain, until they came to a pass, and finally to a narrow path which led to an old cabin. He had found it empty, but there were cans of food and a rifle and many shells. He had remained there a long time—how long he could not tell, for he could only measure time by the cycles of the sun and the moon. Finally he had taken the horse, the rifle and what food was left, and once again started the long journey home. The farther north he went, the more life seemed to have survived. He had seen great herds of horses like his own, stampeding across the plains, and strange birds which he could not identify. Yet he had seen no human beings. every pore. He dried himself and dressed. Conqueror was eating the long grass near the stream. Quickly he saddled him. No time for breakfast. monster. Large greasy scales covered its face and arms, and there was passed over him. It was no use. There was no strength. Only fear—a kind of fear he had never known. He fumbled at his throat, his fingers crawling like cold worms around of strength left him. His shoulders slumped, his head dropped onto his chest. Conqueror trotted away, the sound of his hooves echoing hollowly in the

<question>:
Given that many of the animals in America seem to have a mutation, what is one probable explanation of what may have caused the mutations given that World War III had recently ended?

<options>:
A America experienced a famine that led to animals eating trash and experiencing mutations in later generations.
B There was a nuclear weapon attack in America from an opposing country that led to mutations in animals there.
C America spent all its money on war and neglected its land, which led to mutations in the animals.
D Most of World War III was fought in America, so all the gun powder and resources caused mutations in the animals.

<answer>:

B