Mismatched premises and conclusion. The conditional (”Challengers generally...” is good, but then (A) tries to confirm the necessary (incumbent unpopular) to confirm the sufficient (challenger may win). This is invalid logic. The stimulus negates the necessary to contrapose and conclude that the sufficient is also untrue.

The argument sets a conditional in the domain of fruit salads, qualified by “ordinarily.” The unqualified version would be: If a fruit salad with bananas is not boring, then it contains two or more exotic fruits.” We apply “ordinarily” to this entire rule—”It is typically true that if a fruit salad with bananas...”. The author then negates the necessary condition (does not have two or more exotic fruits) to contrapose and conclude that it will probably be boring

Mismatched premises and conclusion. The conditional (”Traditionally, council meetings...”) is good, but then (C) confirms the sufficient (all zoning) to confirm the necessary (probably poor attendance). This is proper logic, but the stimulus negates the necessary to contrapose and conclude that the sufficient is also untrue.

Mismatched premises and conclusion. (D) sets two separate conditionals (if surviving spouse → estate generally goes to spouse, and if no surviving spouse → estate goes to surviving children), and then confirms one of the sufficient conditions (no surviving spouse) to confirm its necessary (probably goes to children). The stimulus only gives one conditional, and it negates the necessary to contrapose and conclude that the sufficient is also untrue.

Mismatched premises and conclusion. The conditional (”Normally about...”) is good, but then (E) tries to negate the sufficient (percentage of deer population that died was the normal percentage) to conclude that the necessary was also untrue (not unusually mild winter). This is not proper logic. The stimulus negates the necessary to contrapose and conclude that the sufficient is also untrue.