Sentence Correction (SC) | Lacking information about energy use, people tend to

In the correct answer choice, can 'that' refer to 'amount of energy'? Because the subject of the previous clause is people and not amount of energy. For instance, if I say:

The quality of white rice is better than that of red rice. In this sentence, 'that' can refer back to quality because quality is the subject of the clause.

In this OG question, this does not seem to be the case. The subject is people. So how can 'that' refer back to 'amount of energy'?