Identify the Problem/problems Associated with Photovoltaic Cells

Multiple Choice

Identify the problem/problems associated with photovoltaic cells.
I. The semiconductor in photovoltaic cells is doped with small amounts of other elements.
II. Photovoltaic cells are expensive to construct.
III. Photovoltaic cells must absorb large amounts of energy for useful applications.

A) I only
B) III only
C) I and III
D) II and III
E) I, II, and III