Final answer:
Manufacturing is the activity that absorbs most of the labor force of the secondary sector in India, as it involves transforming raw materials into finished products. Construction, agriculture, and mining do not employ as many individuals in this sector.
Step-by-step explanation:
The activity that absorbs most of the labour force of the secondary sector in India is manufacturing. Manufacturing includes the transformation of raw materials into finished products, which constitutes a major part of economic activity in many developing countries as they progress. In contrast, sectors like agriculture belong to the primary sector, mining also falls under the primary sector, and construction, although part of the secondary sector, does not employ as many people as manufacturing does.
In the context of advanced economies, the majority of the workforce tends to be employed in the service industries, which are classified as the tertiary sector. However, India, being a developing economy, has a considerable portion of its workforce in the secondary sector, engaged primarily in manufacturing activities, which have historically generated high value-added profits.