how far should the top of the large target be placed from the top of the small target when conducting final focus on the camera?

For the CTS-3200 and 3210, how far should the top of the large target be placed from the top of
the small target when conducting final focus on the camera?

A.
5 feet (1.52 m) from the top of the small target

B.
7 feet (2.13m) from the top of the small target

C.
10 feet (3.05 m) from the top of the small target

D.
12 feet (3 66 m) from the top of the small target