Question

How did the nuclear era begin?

The Soviet Union developed and used the first nuclear bombs during World War II.
The United States developed and used the first nuclear bombs during World War II.
Both the United States and the Soviet Union developed and used nuclear bombs during World War II.
Both the United States and the Soviet Union developed and used nuclear bombs after World War II.

Answer 1

The United States developed and used the first nuclear bombs during World War II.