Steady is with constant and delight is with verge and agony.
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.
My name is Steve, nice to meet you!
I’m currently 15 almost 16 in June.
I live around 7 minutes from the school.
Currently It’s math, what about you Diana?
I don’t since I’m quite allergic.
