is this sentence "Mrs. Ames is seventy years old, yet she jogs every day."
a.
coordination
b.
subordination
c.
parallelism

This sentence is very tricky because all variants might work. However, you have to pay attention to the punctuation marks: the use of comma makes me think of two contrasting ideas (the adverb 'yet') in parallel viewing. So, I would say that your answer is C.