阅读下列短文，从每题所给的四个选项 （A 、B 、C 和 D ）中，选出最佳选项。

The human brain contains 10 thousand million cells and each of these may have a thousand connections. Such enormous numbers used to discourage us and cause us to dismiss the possibility of making a machine with human-like ability, but now that we have grown used to moving forward at such a pace we can be less sure. Quite soon, in only 10 or 20 years perhaps, we will be able to assemble a machine as complex as the human brain, and if we can we will. It may then take us a long time to render it intelligent by loading in the right software (软件)or by altering the architecture but that too will happen.
I think it certain that in decades, not centuries, machines of silicon (硅) will arise first to compete and then do better than their human ancestors. Once they do better than us they will be capable of their own design. In a real sense they will be able to reproduce themselves. Silicon will have ended carbon's long control. And we will no longer be able to claim ourselves to be the finest intelligence in the known universe.
As the intelligence of robots increases to match that of humans and as their cost declines through economies of scale we may use them to improve environments. Thus, deserts may bloom and the ocean beds be mined. Further ahead, by a combination of the great wealth this new age will bring and the technology it will provide, the construction of a vast, man-created world in space, home to thousands or millions of people, will be within our power.
（1）In what way can we make a machine intelligent?
A.By making it work in such environments as deserts, oceans or space.
B.By working hard for 10 or 20 years.
C.By either properly programming it or changing its structure.
D.By reproducing it.
（2）What does the writer think about machines with human-like ability?
A.He believes they will be useful to human beings.
B.He believes that they will control us in the future.
C.He is not quite sure in what way they may influence us.
D.He doesn't consider the construction of such machines possible.
（3）The word “carbon” (Line 4, Para.2) stands for _________.
A.intelligent robots
B.a chemical element
C.an organic substance
D.human beings
（4）It can be inferred from the passage that _______.
A.after connections with phones, robots will be able to have self-reproduction
B.people have come to realize the possibility of making a machine with human-like ability
C.once we make a machine as complex as the human brain, it will have intelligence
D.robots will have control of the vast, man-made world in space