Which best summarizes the events from the poem contained in these lines?

"when the sun was sunken, he set out to visit
the lofty hall-building, how the ring-danes had used it
for beds and benches when the banquet was over.
then he found there reposing many a noble
asleep after supper; sorrow the heroes,
misery knew not. the monster of evil
greedy and cruel tarried but little,
fell and frantic, and forced from their slumbers
thirty of thanemen"

a. beowulf arrived at the mead-hall and disturbed the sleeping danes.
b. the king asked all the visiting danes to stay the night in the mead-hall.
c. grendel entered the mead-hall and attacked the danes while they slept.
d. the danes were so tired after fighting grendel they fell asleep in the mead-hall.