During the cold war, scientists competed in the "space race."

which revision changes the sentence to draw attention to the object of the action rather than the people or things performing the action?

a. the "space race" by competing scientists occurred during the cold war.
b. during the cold war, scientists led the "space race" competition.
c. during the cold war "space race", scientists competed.
d. the "space race" was a cold war competition by scientist.