D. parallel structure just means that all of your verbs in the comma series line up in regards to tenses, here. in choice D, it's "BE friendly," "INTRODUCE yourself," and "SMILE." these are all present tense verbs.
the rest of the choices don't match--"exercise" and "stretching" are two different verb forms in choice A, "to go to the library" is the odd one out in choice B, ane "to build" doesn't match with the "-ing" verbs in choice C.
Answer:
The Answer Is B
Explanation:
A purveyor Is a person who supplies food and provisions.
Answer:
It's because he sees the future as not as tragic as his past.
Explanation:
The sea is a large body of water
