The correct IUPAC name of 
is:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 1-Bromo-2-methylbutane
For IUPAC naming, choose the longest chain containing the carbon bearing the halogen, number it so that the halogen gets the lowest locant, and write the prefixes in alphabetical order.
The \( \ce{C2H5} \) branch is part of the longest chain: \( \ce{CH2Br-CH(CH3)-CH2-CH3} \), a four-carbon chain (butane) with Br on C-1 and a methyl group on C-2:
\( \overset{1}{C}H_2Br-\overset{2}{C}H(CH_3)-\overset{3}{C}H_2-\overset{4}{C}H_3 \)
The name is 1-Bromo-2-methylbutane.
NCERT (2026-27 edition):
Nomenclature – …
