Final answer:
Evidence C, the reading teacher's testimony of improved test scores attributed to comic book reading, directly supports Colin's claim that comic books can enhance reading abilities.
Step-by-step explanation:
The piece of evidence that supports Colin's claim that reading comic books helps kids become better readers is C: a quote from a reading teacher about how she has seen improvement in the test scores of kids who started reading comic books. This is an expert opinion on the impact of comic books on students' reading abilities. It is this empirical observation that lends credibility to Colin's argument, as opposed to anecdotes or data that do not directly link comic book reading to reading skills.