No flaw. Ending unemployment will end poverty, and ending poverty will end hunger. So ending unemployment will end hunger.

Wrong flaw. (B) is flawed because it commits a cookie-cutter “confusing necessary and sufficient conditions flaw.” Daily exercise guarantees good health, so having good health is a necessary condition of daily exercise. But we can’t infer that daily exercise is required for good health. Attempting to make that inference is confusing sufficiency for necessity. The stimulus, meanwhile, doesn’t commit a “confusing necessary and sufficient conditions” flaw.

No flaw. Getting a professional job requires going to college, and going to college requires graduating from high school. So we can infer that graduating from high school is necessary for getting a professional job.

The argument starts by describing something necessary (keeping good teachers) to improve education. It then describes one approach (improved salaries of teachers) to achieving that necessity (keeping good teachers) and concludes that the approach (improved salaries of teachers) is required to improve education. This commits the same flaw as the stimulus of treating one approach to achieving something as a necessary approach to achieving that thing. Just because we must keep good teachers to improve education, and increasing the salaries of teachers is a way to keep good teachers, that doesn’t imply that we must increase teacher salaries to keep good teachers. There may be another viable approach, eliminating the need for increased teacher salaries.

Wrong flaw. (E) erroneously concludes that increasing a necessary condition (cooperation between law enforcement and schools) of a sufficient condition (preventing abuse of prescription drugs) will ensure the sufficient condition (preventing abuse of prescription drugs). The stimulus, meanwhile, isn’t flawed because of a faulty inference about a sufficient condition and its necessary condition.