(C) "Cleaner and longer-burning than"
The highlighted paragraph is grammatically incorrect and makes little sense in the context because the words "being" and "compared" conflict with the remainder of the sentence's tense structure.
Only C fixes this mistake without introducing a new one (s). The past, present, and future tenses of a verb are available. Things from the past are things that have already occurred (earlier in the day, yesterday, last week, three years ago).
The present tense is used to talk about things that are ongoing or that are currently happening now. Things that are yet to occur are described in the future tense.
Here's another question with an answer similar to this about tenses:
brainly.com/question/11222622
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