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

<passage>:
THE AVENGER By STUART FLEMING Karson was creating a superman to fight the weird super-monsters who had invaded Earth. But he was forgetting one tiny thing—like calls to like. as the beings who have invaded your planet are. I do not comprehend the things which you call hate, fear, joy and love, as they do not. If I went to Earth, I would use your people to further my knowledge, just as the invaders do. I would have no reason to kill the invaders. They are [Transcriber's Note: This etext was produced from suffering, but I could recognize it. "You yourself have said it," I told him. "I am a being of logic, just more nearly kin to me than your people." blood made as it dropped into the sticky pool on the floor. The great banks of machinery around the walls were silent. I knew that they would never come to life again. and alien. It was I who had changed: something inside me was dead, like not solve. Strange, disturbing sensations stirred and whispered within ship out into the carefully-calculated orbit that would be its home. satellite, about the Earth endlessly gathering knowledge into its atmosphere, away from Earth's inexorable gravitational pull, would be a laboratory such as man had never seen. The ship would be filled with the sounds of busy men and women, wresting secrets from the reluctant ether. A new chemistry, a new physics perhaps even a new biochemistry. A discordant note suddenly entered his fantasy. He looked up, conscious of the walls of his office again, but could see nothing unusual. Still, glad that what he had seen was terrible reality rather than even more terrible illusion. INVADERS APPEAR IN BOSTON. 200 DEAD R. Stein, Secretary of the Council, who said in part: "The reason for this ... order must be apparent to all civilized peoples. For the Invaders have spared no part of this planet in their they have terrorized London they have destroyed the lives of citizens in every member state and in every inhabited area. There can be few within reach of printed reports or my words who have not seen the Invaders, or whose friends have not seen them. "The peoples of the world, then, know what they are, and know that we face the most momentous struggle in our history. We face an enemy superior to ourselves in every way "Since the Invaders first appeared in Wood River, Oregon, 24 hours ago, they have not once acknowledged our attempts to communicate, or in any way taken notice of our existence as reasoning beings. They have treated us precisely as we, in less enlightened days, might have treated a newly-discovered race of lower animals. They have not attacked our centers of government, nor immobilized our communications, nor laid siege to our defenses. But in instance after instance, they have done as they would with us. They have examined us, dissected us, driven us mad, killed us with no discernable provocation and this is more intolerable than any normal invasion. "I have no fear that the people of Earth will fail to meet this challenge, for there is no alternative. Not only our individual lives are threatened, but our existence as a race. We must, and will, destroy the Invaders!" Peter sank back in his chair, the full shock of it striking him for the heartbeat they were gone. There were left only two blood-red, malignant monstrosities somehow and below them, a pitiful huddle of flesh no longer recognizable as human beings. They were not dead, those men and women, but they wanted to be. Their bodies had been impossibly joined, fused together into a single obscene, floundering mass of helpless protoplasm. The thin moaning that went up from them was more horrible than any cry of agony. "The Invaders are here, citizens," the commentator was saying in a strangled voice. "Stay off the streets. Hide yourselves. Stay off the streets...." His voice droned on, but neither of them heard it. "Peter!" she said faintly. "Why do they broadcast such things?" "They have to," he told her grimly. "There will be panics and suicides, and they know it but they have to do it. This isn't like a war, where the noncombatants' morale has to be kept up. There aren't going to be any noncombatants, this time. Everybody in the world has to know about them, so that he can fight them—and then it may not be enough." tense abruptly, looked back at the scene. The Invaders were floating The Invaders ignored Peter, staring expressionlessly down at Kanin. in a terrible voice, "Why? Why?" a scream to wake the dead. "But where is she?" Peter complained. "You still haven't explained why months ago." "But why?" Peter whispered. Arnold's strong jaw knotted. "We're hiding," he said. "Everything else has failed." Peter couldn't think of anything to say. Dr. Arnold's voice went on after a moment, musingly. "We're burrowing into the earth, like worms. It didn't take us long to find out we couldn't kill them. They didn't even take any notice of our attempts to do so, except once. That was when a squadron of the Police caught about fifty of them together at one time, and attacked with flame guns and a new secret weapon. It didn't hurt them, but it annoyed them. It was the first time they'd "Since then, we've been burrowing. All the big cities.... It would be an impossible task if we tried to include all the thinly-populated areas, of course, but it doesn't matter. By the time we excavate enough to take care of a quarter of the earth's population, the other three-quarters will be dead, or worse." the hinterland of research. The huge compartments weren't filled with the latest equipment for chemical and physical experiment instead, The Avenger rate is down, in spite of anything we can do. You've seen the figures: we're riding a curve that ends in extinction fifty years from now. "They'll live, and we'll die, because they're a superior race. We're a million years too far back even to understand what they are or where they came from. Besides them, we're apes. There's only one answer." "Out there, in space, the cosmics change unshielded life. They or twelve toes, or a dozen ears—or a better brain. Out of those millions of possible mutations, there's one that will save the human race. We can't fight them they change adult life forms, too. I have one chance in seven of staying alive. You'd have one chance in a million of staying beautiful. I couldn't stand that. I'd kill myself, and then humanity would die, too. You'd be their murderer." Avenger searching for the million-to-one chance. Earth, wondering if the race he had left behind still burrowed in its worm-tunnels, digging deeper and deeper away from the sunlight. But after a time he ceased even to wonder. were searching for." His eyes glowed suddenly in their misshapen sockets. "You are. Your brain is as superior to mine as mine is to an anthropoid's. You solve instinctively problems that would take our mechanical computers hours accidentally drawn one of my talons across his face. "And now," he said softly, "we will go home. I've waited so long—keeping the control chamber and the engine room locked away from you, not telling you, even, about Earth until now—because I had to be sure. But now, the waiting is over. "They're still there, I'm sure of it—the people, and the Invaders. You can kill the Invaders, Robert." He looked at me, a little oddly, almost as if he had some instinctive they are. You can understand them, and so you can conquer them." I said, "That is the reason why we will not go back to Earth."

<question>:
What seems to be the invader's reason for visiting Earth?

<options>:
A They recognize humans as intelligent beings and wanted to see what they have made.
B They want to wage war with Earth and take it for themselves.
C They are investigating humans in a scientific, albeit fatal, way.
D They are investigating humans, making notes to not destroy their world indiscriminately.

<answer>:

C