A `p`-type semiconductor is (i) A silicon crystal doped with arsenic impurity (ii) A silicon crystal doped with aluminium impurity (iii) A germanium crystal doped with boron impurity (iv) A germanium crystal doped with phosphorus impurity.

Options

A. (i) and (ii) are correct
B. (ii) and (iii) are correct
C. (i) and (iv) are correct
D. (i) is correct only.