There are two Ge crystals A and B. Few aluminium atoms are added to A while few lndium atoms are added to B. Then

Options

A. both of them will become n-type semiconductors
B. A will be a p-type semiconductor and B will be an n-type semiconductors
C. both of them will become p-type semiconductors
D. B will become p-type and A will become n-type semiconductor

Answer

C

Explanation

Both Al and Indium are trivalent. Hence when Ge is doped with them, both A and B will become p-type semiconductors.