(A) Primary
The primary sector continues to be the largest employer in India, with more than half of the workers employed in it, mainly in agriculture.
Source: Sectors of the Indian Economy, Chapter 2 — Where are most of the people employed?
The key distinction to remember: tertiary sector contributes most to GDP/GVA, but primary sector employs the most people. Examiners frequently test this contrast. Do not confuse production share with employment share.