How many isomers does pentane have?
The correct answer is: D
Explanation

Isomers are chemical compounds with the same Molecular formula but different structural formula or arrangements of atoms in the molecule.
Pentane, an organic compound with the chemical formula C\(_5\)H\(_{12}\), has three structural isomers:
- n-pentane: A straight chain of five carbon atoms
- 2-methylbutane: A four-carbon chain with a methyl group branching off the second carbon atom
- 2,2-dimethylpropane: A three-carbon chain with two methyl groups branching off the middle carbon atom