Consider the following heavy industries : 1. Fertilizer plants 2. Oil refineries 3. Steel plants Green hydrogen is expected to play a significant role in decarbonizing how many of the above industries?

Green hydrogen can decarbonize all three sectors by replacing fossil-fuel-derived hydrogen in ammonia production (fertilizers) and desulfurization (refineries), and by serving as a carbon-free reducing agent in steelmaking. Option (b) is the most tempting error if one overlooks that hydrogen is a critical chemical feedstock in these specific "hard-to-abate" industries, rather than just a source of heat. The core concept tested is the application of green hydrogen for industrial feedstock substitution to achieve deep decarbonization.