<span>D.the little robin redbreast who befriends Mary
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The first one is the answer
It's in passive voice.
A good rule of thumb for cases like this is that if it has any variation of the verb "to be" (is, was, were, etc.) it's passive voice.
If you wanted to switch it to active voice you need to get rid of "is", and this is usually done by switching the subject and the object (so while in the original sentence, the race car is the doing the verb, to switch it you'd need to make the sixteen-year-old boy be the one doing the verb). This new sentence would be something like:
The sixteen-year-old boy drove the racecar
There are two main ideas for each passage, in the first one it mentions the positive outcomes of having a pet in class; it can help children with health problems and nervousness in students will decrease. In this sentences it supports the idea of a pet in class, saying the positive results of it and how it helps or it will help children.
In the second passage it mentions the negative outcomes of having a pet in class; they will make some health problems worst and the nervousness in students will increase around them. These two ideas are against the possibility of having a pet in class, mentioning how it will affect students instead of helping them.
What makes these two passages different is the opinion towards one main idea: pets in class. One passage supports it and one is against it.
