instruction:
In this task, you're given a context, further information available on a particular linked term from the statement, and an answer term. Your job is to generate a question that can use the information provided to obtain the given answer. You should use the information on both context and link information to create the question. Note that the answer to the question should be exactly the given answer, and if the answer is none, the answer to the question shouldn't be obtainable from the context or linked information.
question:
Context: Strategic Air Command was formed by the United States Air Force after World War II Link Information: headquarters was located at Bolling Field (later Bolling AFB) in the District of Columbia and SAC assumed occupancy of its headquarters facilities until relocating SAC headquarters (HQ SAC) to nearby Andrews Field (later Andrews AFB), Maryland Answer: Andrews Field (later Andrews AFB), Maryland
answer:
Where is the headquarters of the Strategic Air Command?


question:
Context: In 1978, he moved to the Fort Lauderdale Strikers of the North American Soccer League. Link Information: none Answer: none
answer:
Was Marine Cano the starter for the Fort Lauderdale Strikers in 1978?


question:
Context: The spotted green pigeon or Liverpool pigeon (Caloenas maculata) is a species of pigeon which is most likely extinct. Link Information: The animal order Columbiformes is also constituted of pigeons and doves, and includes about 42 genera and 310 species.
 Answer: 310
answer:

How many species of pigeons are there?