What does the passage mainly discus

What does the passage mainly discuss?(A) The role of instinct in animal behavior(B) Observations that suggest consciousness in animal behavior(C) The use of food in studies of animal behavior(D) Differences between the behavior of animals in their natural environments and in laboratory experiments

What does the passage mainly discuss?
(A) The role of instinct in animal behavior
(B) Observations suggest that consciousness in animal behavior
(C) The use of food in studies of animal behavior
(D) Differences between the behavior of animals in Their natural environments and in laboratory experiments