The angle formed by the line of sight with the horizontal, when it is above the horizontal level, is called:
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → Angle of elevation
The line of sight is the line from the observer’s eye to the object seen. When the object is above the horizontal level of the eye, the angle between the line of sight and the horizontal is the angle of elevation: the observer raises the eyes to see it, as when looking up at the top of a tower.

When the object is below the eye, as when looking down from a cliff at a boat, the same angle is called the angle of depression.