Which of the following is an inorganic compound semiconductor?

The correct answer is Option (4) → Indium phosphide (InP)

Semiconductors are either elemental (made of one element) or compound. Compound semiconductors can be inorganic, organic or organic polymers.

Option (1) Silicon (Si) — Incorrect. Silicon is a single element. It is an elemental semiconductor, like germanium.

Option (2) Anthracene — Incorrect. Anthracene is a compound semiconductor, but it is organic.

Option (3) Polyaniline — Incorrect. Polyaniline is a semiconducting organic polymer.

Option (4) Indium phosphide (InP) — Correct. InP is made of indium and phosphorus. It is an inorganic compound semiconductor, in the same group as CdS and GaAs.

NCERT (2026-27):
Classification of Metals, Conductors and Semiconductors – “(ii) Compound semiconductors: Examples are:
• Inorganic: CdS, GaAs, CdSe, InP, etc.”