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 Birds and the Bees Which goes to prove that, in some Extensive research did not uncover any evidence that the U.S. copyright on this publication was renewed.] to me that many cling tenaciously, and ignorantly, to the old religion. But of course there were no cousins. There was nothing. And Man returned, and settled down to live. Saddened, but resigned and content to live in peace with his knowledge and his power. Gone now are all the ancient evils, wars, emergencies. states, quite prevalent among members of the race long ago, and are seldom seen today. Indeed, Melia was on this account made the butt of many jokes and, I fear, would have had a lonely life of it had it not been for the friendship of Xeon. warning, continued to rise, and then—poof. Everything has evaporated in Maternite. All the Prelife is gone." "There is nothing left," Melia insisted. "Can more be made? And if not, what will happen with no more children?" consternation. And can the simple people be blamed? They were aware indeed, an emergency. For a machine had failed! Not in the memory of the eldest among us has a machine failed. They were created so long ago, indeed, that the ignorant believe them to have been constructed by the gods themselves. And never, so far as I know, has one failed. Small wonder that the watcher had been negligent. Indeed, the watcher is more a tradition than a necessity. assembled to hear. By this time, unfortunately, many of the Conclave had departed for home and supper. Yet perhaps it is for the best, for those left were the most earnest and intelligent. "I would not bore you," he said, "with details of which only the gods are sure. Know, then, that once granted a few cells of Prelife, it is thus assuring us, as has always been, a continuous source of Prelife to be born by the Generating Machine as children. The machines bear the exact number of children each year to balance the number of us whom the gods claim. Such it has always been from time immemorial." A murmur of assent and approval of these virtuous words whispered actually failed." Cries of "Treason" sprang up, and I fear it might have gone hard for the priest had I not been able to insure order. "That is not the worst," he cried, as if in defiance. "All the Prelife has been dried up. It will not function. There is no more. And there will be no more children!" At this I feared the Conclave was about to riot. It is at such times that I most revere the wisdom of the ancients, who decreed seventy years the minimum age for a member of the Conclave. They shouted and roar like a youngster? They quieted, breathing heavily, and I asked, "Is there no way, then, to produce more Prelife in order that the machines may produce more children for us? "As I have said," he replied, "give the machines but a bit of Prelife and they will produce more. But take away that least bit, and they are helpless." been a beginning to Prelife? For the Machine, it seems, cannot make it "Riddles are not called for," I answered severely. "Are not riddles often the beginning of knowledge?" he asked, in that irritating dumber-than-thou attitude of his. "Must there not, long ago, have been a source of Prelife: a source now forgotten? And may it not even now—should we discover it—be available to us? I am reminded of the story of the animals of old—" "I know well the legend of the animals, but what does it have to hastened to explain the legend of the animals. "It is said that many thousands of years ago, time without reckoning, there existed on the earth creatures who were alive like us, and yet not like us. It is said although not mute, they could not speak." Rocsates' voice made itself heard. "It is true. Such creatures did men—if it were so, then, what of it?" "May it not be," Rocsates put in, "that these animals had no machines to reproduce their kind? For surely the gods would not grant machines to such creatures. And indeed, if they had Maternite Machines, why then we would yet have these animals among us." "And how, then, did these animals reproduce?" I asked. Machine, and that at such a time both the animals and Men reproduced At this two members of the Conclave fell immediately into a faint, and and so delicate, that they are kept in an air-tight tomb lest, being handled, they be destroyed and all knowledge within them lost. Therefore, they have not been read in the known history of our race. "Some of those among you are She's," he began. "And you know you are different from the rest of us. To the advantage, your skin is fairer and your features more often handsomer than ours. To the disadvantage, your excretory system is not so mechanically dextrous as ours. And, you may say, why should this not be so? There is, indeed, no reason why we should all be identical. Perforce you have the advantage, perforce we exist no reason for this? Was there not, perhaps in ancient times, a discovered: Then reproduction was carried on by individuals, without help of the then nonexistent machines. The She's are not wanderers from another land, but they have lived with us for all time they are not another race, but we are all types of one race. And the fact of reproduction is somehow intimately related to the physical distinctions of the She's!" These last sentences were shouted to be heard above the roar of the "In fact," Rocsates added, sitting down, "this process of reproduction seems to have been so simple that there was once a problem of over-population." Order was lost among the Conclave as each man turned to speak to his neighbor, and for some time I could not restore order. I realized that something had to be done to save Rocsates before the outrage of the assembled overwhelmed him. such there was, I was hopeful of dismissing the entire affair with no harm done. "For if people reproduced too often, why then this reproduction must have been a pleasant thing to do otherwise they where is the necessity for the machines, and why were they created?" Rocsates seemed perplexed by this problem, whereupon Xeon, who together the process of reproduction was of ruled it to be a sin? And therefore the machines were necessary!" At this impudence the Conclave dissolved in an uproar, and I was beyond however, I had to admit that his supposition was a possibility, and appearance—he looked as if he had not slept of late, nor eaten either. His eyes were sunken, and his features had doubled in age. He was bent formalities were over. I intended to speak for Xeon, but Rocsates was "I have indeed discovered the secret of reproduction," he began. "After but it seems to mean...." His words trailed off. He was obviously When he finished the Conclave sat in horrified silence. His words, to move. I cleared my throat. "Shall not these organs which you mention have atrophied by now? With no use throughout all these generations, will they not have evolved into nothingness?" "I do not think so," Rocsates replied after a while. "What to us is an eon, to evolution is but an instant. And then the swelling of the breasts, I believe, proves that there is still reproductive activity in breasts. Melia has volunteered, on condition that Xeon be released from I voiced my assent, and the entire Conclave adjourned to the fields. "They seemed finally to accomplish all the book described," I muttered. a time lapse which is necessary. The child does not appear immediately." "It doesn't matter," I said disconsolately. "Who could ask them to go through such an ordeal again?" My heart has a warmth in it, and I no longer fear for the future of our race when our young people can show such nobility and sacrifice.

<question>:
Since humans stopped reproducing among themselves, what has been the greatest impact on human biology?

<options>:
A significant reduction of the appearance and function of sex organs
B more predictable measures for increasing the global population
C gradual decrease in the overall intellectual quotient of a society
D a lower prevalence of birth defects and learning disabilities

<answer>:

A