The correct answer is B. He is cruel. Grendel is introduced as a bloodthirsty, evil monster. He is a lonely creature who seeks an understanding of the seemingly meaningless world around him. He kills men consistently in the town's mead-hall, ripping them apart. Grendel is shown as evil because he kills passionately.
I mean this is more ao but Fifty shades of Grey is pretty similar to the concept you’re describing.
Assuming we're just looking at this phrase, "learn'd" suggests that the astronomer studied to become intelligent in the astronomical field.
