Many people at that time believed that spices help preserve food

Many people at that time believed that spices help preserve food; however, Hall found that many marketed spices were ____ bacteria, moulds and yeasts.

A. devoid of
B. teeming with
C. improved by
D. destroyed by
E. active against

The answer is B. My question is what is the problem with the D?

Because of the word “however”, which introduces the last sentence that proves the idea of the first sentence wrong: they thought that spices were good for preserving food, but spices are full of bacteria and therefore can’t be good.