The population of blue fin tuna has dropped greatly because fishermen are ignoring fishing limits. Why do fishermen illegally catch too many blue fin tuna?

A.
It is a beautiful species of fish that is commonly used for household decoration.
B.
Fishermen are accidentally catching blue fin tuna while fishing for other species.
C.
Blue fin tuna are predators of a valuable fish that fisherman want to catch.
D.
Blue fin tuna are considered a delicacy in many places, making them quite valuable.