Why do you think marathon runners / athletes eat a meal rich in carbohydrates the day before the race?​

Explanation:

Carbohydrates produce energy and if the energy is not used it gets stored as fat therefore when the athletes race they use the fat stored (I think)

type of error:

the error in the sentence is a "dangling modifier". a dangling modifier is a phrase, word or clause that "dangles" because there is not target to modify. in this case, "after mopping the floor" is the dangling modifier since it has no word to modify. the noun "house" cannot mop the floor; therefore there is a mistake in the writing of the sentence.

b is the answer.   i sat on the lumpy sofa, totally exhausted, with a bad taste in my mouth, wondering what i should do next.