When does history begin？ It is tempting to reply 'hi the beginning", but like many obvious

answers, this soon turns out to be unhelpful. As a great Swiss historian once pointed out in another connection, history is the one subject where you cannot begin at the beginning, ff we want to, we can trace the chain of human descent back to the appearance of vertebrates, or even to the photosynthetic cells which lie at the start of life itself. We can go back further still, to almost unimaginable upheavals which formed this planet and even to the origins of the universe. Yet this is not "history".

Commonsense helps here: history is the story of mankind, of what it has done, suffered or enjoyed. We all know that dogs and cats do not have histories, while human beings do. Even when historians write about a natural process beyond human control, such as the ups and downs of climate, or the spread of disease, they do so only because it helps us to understand why men and women have lived (and died) in some ways rather than others.

This suggests that all we have to do is to identify the moment at which the first human beings step out from the shadows of the remote past. It is not quite as simple as that, though. We have to know what we are looking for first and most attempts to define humanity on the basis of observable characteristics prove in the end arbitrary and cramping, as long arguments about "apemen" and "missing links" have shown. Physiological tests help us to classify data but do not identify what is or is not human. That is a matter of a definition about which disagreement is possible. Some people have suggested that human uniqueness lies in language, yet other primates possess vocal equipment similar to our own; when noises are made with it which are signals, at what point do they become speech？ Another famous definition is that man is a tool-maker, but observation has east doubt on our uniqueness in this respect, too, long after Dr. Johnson scoffed at Boswell for quoting it to him.

What is surely and identifiably unique about the human species is not its possession of certain faculties or physical characteristics, but what it has done with them--its achievement, or history, in fact. Humanity’s unique achievement is its remarkably intense level of activity and creativity, its cumulative capacity to create change. All animals have ways of living, some complex enough to be called cultures. Human culture alone is progressive: it has been increasingly built by conscious choice and selection within it as well as by accident and natural pressure, by the accumulation of a capital of experience and knowledge which man has exploited. Human history began when the inheritance of genetics and behavior. which had until then provided the only way of dominating the environment was first broken through by conscious choice. Of course, human beings have always only been able to make their history within limits. These limits are now very wide indeed, but they were once so narrow that it is impossible to identify the first step which took human evolution away from the determination of nature. We have for a long time only a blurred story, obscure both because the evidence is poor and because we cannot be sure exactly what we are looking for.

According to the author, when should be regarded as the beginning of human history？

A．The appearance of vertebrates.

B．The point when human beings consciously chose to do something.

C．The coming into being of the photosynthetic cells.

D．The origins of the universe.