The terrestrial telescope has one extra lens more than the astronomical telescope. The extra lens is for?

A. improving the sharpness
B. creating an inverted image
C. magnification of the image
D. erection of the image

Correct Answer:

Option D – erection of the image

Explanation

The extra lens in the terrestrial telescope mounted at the middle between the objective lens and the eyepiece is to re-invert the image so that it is upright.