The great triumphs of technology and exploration begin as the dreams and hypotheses of bold thinkers. As economic and environmental pressures build on Earth, the dreams—a satellite, men and women in space, the first walk on the moon and Mars, space stations, and a shuttle—become an essential alternative.
(A)Bold dreams and hypotheses produce technological success and explorations into the space.
(B)Economic and environmental pressures will be replaced by explorations into the space.
(C)Technology and exploration into space initially take the form of dreams and hypotheses, but become an alternative when Earth encounters problems.
(D)Satellites, space stations, shuttles and other extraordinary adventures result in the dreams and hypotheses of bold thinkers.