When the united states dropped atomic bombs on japan, it triggered the start of a race between the united states and the soviet union. this was a key issue during the cold war.

a. nuclear arms
b. space travel
c. climate change
d. global peace

The correct answer is option A. "Nuclear Arms".

Explanation:

When United States dropped atomic bombs in Hiroshima, and three days later in Nagasaki, it marked the end of World War II. This also marked the start of a nuclear arms race between the two dominant forces of the world: United States and the Soviet Union. This nuclear arms race was a key issue of the Cold War, having a series of tests that increase the tension between the two countries who looked for supremacy in nuclear warfare.

c.

worked constantly and gave many sincere speeches about the importance of independence