Step 1: Contrast with the First Plan:
Recognise the deliberate pairing used across this exam: Q18 asks about the First Plan (agriculture-focused) and this question asks about the Second Plan, which pivoted the other way.
Step 2: Evidence:
The public-sector steel plants and capital-goods industries set up in this period are the standard textbook evidence for an industry-first strategy.
Step 3: Final Answer:
Industry.