Sharks Do Not Have a Swim Bladder, and Counteract the Tendency

Sharks do not have a swim bladder, and counteract the tendency to sink by

A) secreting gas into the body cavity to provide buoyancy.
B) active movement of the tail muscles to produce upward force.
C) adjusting body volume by taking in water.
D) using the pectoral fins as a hydrofoil to produce dynamic lift.
E) increased body fat which adds to buoyancy.