Identify the correct name of the given structure.

The correct answer is Option (1) → 4,4'-dichlorodiphenyltrichloroethane

The structure is DDT, the first chlorinated organic insecticide. Its main chain has two carbon atoms (ethane): one carries three Cl atoms (\( \ce{CCl3} \)), the other carries an H and two phenyl rings, each with a Cl at the para position:

    \( \ce{CCl3-CH(C6H4Cl)2} \) (Cl of each ring at the para position)

Hence the name p,p′-dichlorodiphenyltrichloroethane, i.e. 4,4′-dichlorodiphenyltrichloroethane (IUPAC: 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane).

NCERT (2026-27 edition):
p,p′-Dichlorodiphenyltrichloroethane (DDT) – “DDT, the first chlorinated organic insecticides, was originally prepared in 1873, … The use of DDT increased enormously on a worldwide basis after World War II, primarily because of its effectiveness against the mosquito that spreads malaria and lice that carry typhus.”