In the late 1960s, the united states and the soviet union adopted a foreign policy of détente. however, many people doubted that the soviet union was interested in real change. the leader of the soviet union, leonid brezhnev, continued to a. treat the space program as a potential weapon during the period of détente. b. refuse to meet with the foreign leaders during the period of détente. c. build up his country's military power during the period of détente. d. refuse to sign anti-nuclear agreements during the period of détente.

C.build up his country's military power during the period of détente.

Brezhnev met with American presidents Nixon and Ford and signed nuclear arms limitations agreements with them.  And also during the Nixon and Brezhnev years, the US and USSR participated in a joint mission in space, the Apollo-Soyuz Test Project.

But military buildup continued in great measure under Brezhnev -- from the Soviet view, to keep pace with American power.  Defense spending increased 40% during Brezhnev's early years, from 1965 to 1970, and continued to increase annually thereafter.  The "Brezhnev Doctrine" called for the Soviet Union to intervene anywhere that socialist government was threatened, so there were military deployments outside of the USSR, in places like Czechoslovakia and Afghanistan.