What is the most accurate description of how Beowulf's fight with Grendel's Mother transpired?

Beowulf struggles initially when his sword breaks, but kills her using a giant's sword instead

Beowulf immediately overpowers her with his superhuman strength, but he regrets killing her

Beowulf takes pity on her because she is mourning her son, but he eventually kills her

Beowulf finds his courage wavering as he enters the lair, but he eventually faces his fears and kills her

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