The __________ of a CCTV lens defines its effectiveness in viewing objects from a horizontal and vertical view. The focal length value relates to the angle of view that can be achieved. ________focal length lenses provide wider-angle views, while _______ focal length lenses provide a narrower view.

A.
Focal length, long, short

B.
Focal length, short, long

C.
Varifocal, short, long

D.
Varifocal, long, short

Explanation:
The focal length of a lens defines its effectiveness in viewing
objects from a horizontal and vertical view. The focal length value relates to the
angle of view that can be achieved. Short focal length lenses provide wider-angle
views, while long focal length lenses provide a narrower view.