Answer:
Option B,

Explanation:
Given -
The submerged vessel travel horizontal distance above the shipwrecked hull

kilometers
The vertical distance from the the shipwrecked hull to the ground is equal to
kilometers
There forms a right angled triangle with
Base
kilometer
Perpendicular
0.4 kilometer
Tan (angle)

Substituting the given values we get -
Angle of depression

Hence, option B is correct.