Research Observatories Do NOT Use Newtonian Reflectors Because They

Multiple Choice

Research observatories do NOT use Newtonian reflectors because they

A) cannot be made large enough for modern astronomical work.
B) are inherently lopsided and cannot support heavy research instruments.
C) are more sensitive to atmospheric distortions than are refractors.
D) require two mirrors, whereas the Cassegrain requires only one.