Question

the united states and european countries should do more to support regional defense cooperation in the black sea and help ukraine reform and modernize its armed forces and security services. in this sentence, cooperation means: reduction of weapons an increase in price joint action the act of becoming visible

Explanation:

The word "cooperation" generally refers to people or entities working together. In the context of regional defense, it means joint action among countries for defense - related purposes.

Answer:

C. joint action