Yes, it's a dependent clause.
The correct answer is D): The author argues that, despite the cost, the group most likely to be advocates for the thermometer pill are parents of athletes.
In the excerpt, the author claims that parents are willing to spend the $50.00 that a pill costs if it helps them protect their childrens lives on hot days.
<span>He was having a fun time with you're uncle at the beach.
The mistake is this sentence uses "you're" which means 'you are'
</span>
<span>He was having a fun time with you are uncle at the beach
makes no sense.
The correct sentence is </span>
<span>He was having a fun time with your uncle at the beach
</span>
