English morphological rules detail how words relate to other words. Thus, my best assumption would be because BOLDEST is an adjective whereas BOLDLY is an adverb.
This doesn't necessarily have a technical term, it is best known as Musical Nationality
Answer:
He was born on May 23, 1999
Explanation
Answer:
C) It is played with a bow
That is the only one I know so far. I will let you know when I find out more.