Final Answer:
The Air Force tested new ideas and technologies in crisis support missions during the 1990s.
Step-by-step explanation:
The correct decade for the Air Force testing new ideas and technologies in crisis support missions is the 1990s. This aligns with historical events and military activities during that time frame.
Crisis Support Missions, The question specifically refers to crisis support missions. During the 1990s, the U.S. Air Force was actively involved in various crisis situations, including humanitarian aid, peacekeeping, and response to regional conflicts.
Explanation Exclusion, Other decades are not valid answers based on historical context. The 1980s witnessed Cold War tensions, and the 2000s were marked by the global war on terror, with a focus on counterterrorism operations rather than crisis support missions.