Final answer:
Beowulf responds to Grendel's attack by engaging in a fierce battle with the monster and ultimately defeating him, showcasing his heroic qualities in the epic.
Step-by-step explanation:
In the epic poem Beowulf, Beowulf responds to Grendel's attack on his fellow Geat by fighting fiercely. Option c) He fights fiercely and defeats Grendel is the correct answer. When Grendel attacks Heorot, the hall of the Danes, Beowulf, a warrior of the Geats, confronts the monster. He does so with great bravery and without the use of weapons because Grendel is not known to use them. This epic battle is one of the most famous scenes in the poem, showcasing Beowulf's strength and heroism as he eventually defeats Grendel, fulfilling his promise to rid the Danes of the terror inflicted by the monster.