Most fishes do not sink in water because of the presences of:
I. swim bladder
II. air bladder
III. air sacs
IV. air in spongy bones
A.
II and III are correct
B.
I and II are correct
C.
I, II, III, and IV are correct
D.
III and IV are correct
Correct answer is B
Fishes have a swim bladder or air bladder which helps them to remain buoyant without sinking in water. They are present in the body cavity.
