Migrating Birds Often Cross the Gulf of Mexico in a Single

Multiple Choice

Migrating birds often cross the Gulf of Mexico in a single flight, and their flight muscles demand extreme endurance. An examination of the muscles used to perform this activity would show that they

A) have substantial reserves of fuel.
B) have low levels of ATPase activity.
C) are well-supplied with blood vessels.
D) have many mitochondria.
E) All of the above