Yes
It uses a lot of commas where you can easily put periods, and it uncomfortably merges multiple sentences into one
The sentence that contains an unnecessary shift in verb tense is the second one - Lee noticed a problem and alerts a teacher.
It should be <em>alerted, </em>which is the past tense as the first verb <em>noticed.</em>
in that paragraph, the expression Mounting evidence could be a bit confusing, but it indicates that there's been reaserch about it before, and that it all points in the same direction, the more research proving the same point means the data is convincing. The answer is D.