Explanation:

Option 1 suggests that green hydrogen would only be useful in decarbonizing one of the industries listed, but this is incorrect as all three industries can benefit from it.

Option 2 says that green hydrogen would benefit only two of these industries. This is also inaccurate because fertilizer plants, oil refineries and steel plants have significant carbon emissions that can be mitigated with green hydrogen.

Option 3 is the correct answer. Green hydrogen can play a crucial role in decarbonizing all three industries: fertilizer plants, oil refineries, and steel plants. This is because green hydrogen is a clean-burning fuel and feedstock, which can reduce reliance on fossil fuels.

Option 4 is incorrect as it suggests that green hydrogen has no role in decarbonizing these industries, which goes against the rising emphasis on green hydrogen as a solution for lowering greenhouse gas emissions.