The correct answer is "ignore."

"Snub" is a verb that means to rebuff, ignore or spurn disdainfully, making "ignore" a synonym of "snub."

The correct answer is "disprove." 

"Refute" is a verb that means to prove wrong.

"Omit" means to exclude, to leave something out, to edit something out or eliminate it.

"Sanction" means to allow, to permit, to approve.

"Regard" means to look at something, or it can mean to judge something or to consider something.

"Mislead" means to give somebody incorrect information, to lie, to dupe.

"Conclude" means to finish or come to an end; it can also mean to decide.

Align means to arrange in a line.

Forage means to scavenge.

One meaning of "fumble" is "to search for something by reaching or touching with your fingers in an awkward or clumsy way," we need to pick out an answer choice that means something like "search for." While both "search blindly" and "look quickly" could mean "search for," "search blindly" is the better answer because "blindly" conveys the "awkward or clumsy way" of searching that "fumble" conveys.

"Mar" is a verb that means "to ruin the beauty or perfection of something" or "to hurt or damage the good condition of something," so we need to pick out a word that means something like "to ruin" or "to damage." Since one meaning of "spoil" is "to have a bad effect on something" or "to damage or ruin something," "spoil" is closest in meaning to "mar" of the given answer choices, so it is the correct answer.

"Encroach" is a verb that means "intrude on a person's territory or a thing considered to be a right," we need to pick out another verb that means "intrude on." While "enroll" sounds like "encroach," "enroll" means "officially register as a member of an institution or a student on a course"; since it does not mean the same thing as "encroach," it can't be the right answer. "Trespass," however, means "enter the owner's land or property without permission" or "commit an offense against (a person or a set of rules)." Since the first meaning of "trespass" is similar to the meaning of "encroach," "trespass" is the correct answer.

"Amble" is a word that means "walk or move at a slow, relaxed pace," so we need to pick out another word that means "walk," and more specifically, "walk at a relaxed pace." While "scamper," "run," and "dash" all refer to movement, they refer to quick movement, not a form of movement that is "at a slow, relaxed pace." Only "saunter," which means "to walk about in an idle or leisurely manner," means "to walk" and includes the connotation of the movement being relaxed and "leisurely." Because of this, "saunter" is closest in meaning to "amble" of the given answer choices, so "saunter" is the correct answer.

"Wilt" is a verb that refers to plants and means "become limp through heat, loss of water, or disease." So, we need to pick out another verb that means something like "become limp." While "droop" and "limp" might both look like potentially correct answers, "limp" cannot be the correct answer because while "wilt" means "to become limp," "limp" as a verb does not mean "become limp" - it means "walk with difficulty, typically because of a damaged or stiff leg or foot." So, "limp" cannot be the correct answer. "Droop," however, means "bend or hang downward limply," so "droop" is the correct answer because it is the answer choice closest in meaning to "wilt."