**Allotropy** is a special case of polymorphism that applies to:
ACompounds only
BElements only (e.g. carbon as diamond/graphite/fullerene)
CBoth compounds and elements
DMixtures
Answer & Solution
Correct answer: B. Elements only (e.g. carbon as diamond/graphite/fullerene)
Allotropy = polymorphism in **elements**. Carbon allotropes: diamond, graphite, fullerene (C₆₀). Phosphorus has white, red, black allotropes. Sulphur: rhombic, monoclinic.
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