What roles did Henry Kissinger hold in the U.S. government?

Henry Kissinger served as both the National Security Advisor and the Secretary of State, making option B the correct choice. His tenure in these positions spanned critical periods during the Cold War, especially during the Nixon administration. As National Security Advisor from 1969 to 1975, Kissinger played a pivotal role in shaping U.S. foreign policy, particularly in relation to China and the Soviet Union. He is well-known for his part in the policy of détente, aimed at easing tensions between the superpowers.

Following his role as National Security Advisor, Kissinger became Secretary of State in 1973, continuing to influence U.S. diplomacy and negotiations globally. He was heavily involved in critical peace negotiations, such as the Paris Peace Accords, which aimed to bring an end to the Vietnam War.

The other options do not accurately reflect the roles held by Kissinger. He was never Secretary of Defense, Chief of Staff, President, Vice President, or held positions within the CIA as indicated in the other choices. Consequently, his primary contributions and significance in U.S. history are tied specifically to his roles as National Security Advisor and Secretary of State.