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

<passage>:
fight for a race of which they had never heard. swamp snake. Their clear red skin had become blotched and purple, their thatched huts, the strange people who lived in these huts instead of villages, he was satisfied to travel home again. He was a man of the world now, weary of exploring and ready to settle down. He was anxious to see his family again, his father and mother and all his brothers and sisters to sit round a fire with them at the entrance to their cave and tell of the wondrous places he'd visited. And, most of all, he wanted to see Na, graceful, dark eyed Na, whose easy, as the loping of Shee, the great cat. figures. He could see the rat man plainly now—his fanged, frothy furry face and twitching tail. The Oan, however, was too intent the red men's arms. the ground. "Since a long time," she answered sadly. Then she cried. And between sobs she spoke: landing in the valley below. Many colored fire spat from one end of it. "The men of our tribe snatched up stones, and holding one in their white as the foam on water, and clothed in strange garb from the neck down, even to coverings on their feet. They made signs of peace—with one hand only, for they carried weapons of a sort in the other. And the men of our tribe made the same one-handed sign of peace, for they would not risk dropping their stones. Then the white men spoke but their tongue was strange, and our men signaled that they could not understand. The white men smiled, and a great miracle took place. Suddenly to our minds came pictures and words. The white men spoke with their thoughts. "They came from a place called Earth, they said. And they came in "There were two more white ones who came from the sphere. One was a woman with golden hair, and the other, a man of age, with hair like silver frost. "There was a great feast then, and our men showed their skill at burn the wood in two. We were indeed glad they came in peace. "That night we asked them to sleep with us in the caves, but they made everywhere a red man showed himself, he cried out and died by the flame from the white men's weapons. our friends in the night and were using their weapons to attack us. There was a one-sided battle that lasted three days. Finally, under and those of us who lived still travel alone." Ro groaned aloud as Na finished her tale. His homecoming was a meeting with tragedy, instead of a joyful occasion. "They have the weapons of the white ones." "And the white ones, as well. They probably keep them alive to repair Together we will fight the rat men." but Ro could make out four prone figures. They appeared to be white blots in the dimness. One had long, golden hair, like spun clasped on Na's wrist. "All men will know now that you are the mate of Ro," he whispered. And he kissed her, as was the custom of his tribe when a man took a wife. Without another word he disappeared over the edge of the cliff. They had already made plans for their next meeting. There was no need for a prolonged farewell. They would be together soon—on the far side of the cliff—if all went well. In his left hand and under his armpit Ro carried stones. They were of a the presence of many Oan close by. The hair at the base of his neck Suddenly he halted. A dim figure approached. It was one of the Oan, a When they were ready, Ro signaled the four white people to follow him. shadows. The progress they made was slow, but gradually the distance between longer necessary. The four white people stumbled ahead more quickly. "Who is Na?" asked the girl. "She is the one I have chosen for my mate," Ro answered. The white girl was silent. They traveled quite a distance without Finally the man with the silver hair asked, "Why did you risk your life "With your help I will avenge the death of my father and brothers and the men of my tribe." He stopped walking and stared around him for a landmark. They had the Oan." "But there are only six of us," one of the white men protested. "There Ro smiled. "We will speak of that when it is dawn again," he said with his the white ones. The man with the silver hair seemed very old and weak, but very wise. The other men had hair as black as any Martian's, but their skin was pure white. They were handsome, Ro thought, in a barbaric sort of way. One was lean and determined, the other, equally determined, but stouter "We come from a place called Earth, many millions of miles away introduction—"and myself are an expedition. We came here to Mars to "Our part of Earth, America, is a great country. Our cities are built what is it like here on Mars? Surely the whole planet isn't wilderness. What year is it?" don't understand." "A year is a measure of time," the old man explained. "When we left Earth it was the year twenty-two hundred." "We have nothing like that here," said Ro, still puzzled. "But tell me, about this speaking with the mind. Perhaps I shall understand that." "It's simple telepathy. We have mastered the science on Earth. It takes because of action we have in mind as we speak. We want the other to walk, we think of the other walking. A picture is transmitted and a short distance away. Her arms were loaded with Manno, the fruit of Mars, and clusters of wild berries and grapes. "You see," she said, "I will make you a good mate. Our table will be well provided for." "You will make no mate at all," Ro said sternly, "and there will be no fortunate." He glared at her for a moment, then smiled and helped her with her Ro smiled. These young white men were no different than Martians where When they had finished breakfast, they sat around the floor of the cave and spoke. the rat men?" "The Oan are cowards," Ro answered. "They are brave only because they "You're lying," he shouted aloud, forgetting that the white man You refuse to help me avenge my people because you are more of a coward "He's lying," said Ro with his thoughts. He repeated his plan to the others. "But they'll kill her," gasped Charlotte. "She will be a woman alone," said Ro. "The Oan prefer to capture women "Why me?" Grimm demanded. "Why not Carlson? Or are you saving him for "This is no time for fighting," he said. "When the Oan are defeated you can kill each other. But not until then." "Okay," he sneered. "I'll go with the red man. But when we meet again, be trapped. They would die under a hailstorm of rock. "You would have liked a more tender goodbye with Charlotte," Ro said to Carlson straightened. He weighed Ro's words before answering. Finally he said, "I didn't want to make trouble. It was a bad time, and senseless, besides. Charlotte and I are planning to be married when we return to America. It's not as though Grimm was still in the running. I'm sure he'll see reason when we tell him. It's foolish to be enemies." "Why don't you take her for your wife here on Mars? That would end the trouble completely." Carlson seemed surprised. "It wouldn't be legal. Who would perform the ceremony?" Ro seemed puzzled, then he laughed. "Last night I thought that we on Mars are backward. Now I'm not so sure. When we find our mates here, we take her. There is no one to speak of 'legal' or 'ceremony.' After all, it's a personal matter. Who can tell us whether it is 'legal' or not? What better ceremony than a kiss and a promise?" He bent back to his work chuckling. "I could argue the point," Carlson laughed. "I could tell you about a place called Hollywood. Marriage and divorce is bad enough there. Under your system, it would really be a mess. But I won't say anything. Here on Mars your kiss and a promise is probably as binding as any ceremony." Ro didn't speak. He didn't concentrate and transmit his thoughts,

<question>:
What is NOT a difference between the red people and the humans?

<options>:
A their typical mode of communication
B the importance of tracking time
C the dynamic between males and females
D their marriage ceremony

<answer>:

C