Answer: Option B
Explanation:
Norton enjoys most of the mystery novels he reads because it is stated that 80% of the mystery novels he reads has believable solutions ,80% represents most of the mystery novels he reads and has believable solutions .he also stated that he doesn't enjoy mystery novels that doesn't have believable solutions, with this, we can conclude that these novels that don't like believable solutions constitute 20% of the novels he read.
From the above analogy, it can be inferred that Norton enjoys most of the mystery novels he reads because they constitute 80% of the believable solutions that makes him like them.