Q.The three-domain system of classifying life into Bacteria, Archaea and Eukarya was proposed by:

[!TLDR] Carl Woese proposed the three-domain classification based on molecular (rRNA) evidence. [!ANSWER] (c) Carl Woese.

In 1977, microbiologist Carl Woese, comparing ribosomal RNA sequences across organisms, found that a group of prokaryote-like organisms was genetically distinct enough to warrant its own domain (Archaea), leading to the three-domain system: Bacteria, Archaea and Eukarya. Linnaeus (a) is associated with binomial nomenclature and early classification; Whittaker (b) proposed the five-kingdom system; Haeckel (d) proposed an early three-kingdom system. [!ANSWER] The correct option is (c) Carl Woese.

Match the scientist to the specific classification scheme named in the question, distinguishing Woese's domain-level scheme from Whittaker's kingdom-level scheme.

Students often mix up Woese (three domains) with Whittaker (five kingdoms) since both are classification schemes taught close together.