“Redoubtable” is an adjective that means “formidable” when referring to a person, so we need to pick out an answer choice that means something like “formidable.” That means that “pathetic” cannot be the correct answer, because “pathetic” means “arousing pity,” making it a near antonym, not a synonym, of “redoubtable.” “Daunting,” however, is an adjective that means “intimidating,” and because “daunting” is the answer choice closest in meaning to “redoubtable,” “daunting” is the correct answer.

When someone "surpasses" something such as a world record in running, it means they "exceed" the previously set limit or expectation. The other answer chocies are as follows: to "summit" is to reach the peak; to "regress" is to go backwards; to "undermine" is to weaken; and to "neutralize" is to counteract.