Da first problem is D. 2nd is C
The subordinate clause is : " which had been dumped into the city water system "
The author's main purpose was the explain that the Community Service Council was effectual to high school students. The personal backstory was to add more evidence of the effectiveness.
I don't see any underlined words in the sentence. However, I'll just post my answer based on my understanding.
Where there is water ⇒ subordinate clause
There are mosquitoes ⇒ independent clause
Independent clause is a complete sentence. It has a subject, a verb, and expresses a complete thought.
Subordinate clause is a dependent clause that starts with a conjunction. It also has a subject and a verb but it is dependent on the main clause.
Answer:
Activating background knowledge. Research has shown that better comprehension occurs when students are engaged in activities that bridge their old knowledge with the new. ...
Questioning. ...
Analyzing text structure. ...
Visualization. ...
Summarizing.