Which personal pronoun agrees with the antecedent in this sentence? only one of those giant dogs is wagging tail. a. their b. its c. it's

The scowl grew blacker on his face; the indigo-circles enlarged round his eyes as the storm-rings round the midnight moon. He sprang upon me; his tri-forked thing at my heart.

I seized it; I snapped it; I dashed it; I trod it; and dragging the dark lightning-king out of my door, flung his elbowed, copper scepter after him.

But spite of my treatment, and spite of my dissuasive talk of him to my neighbors, the Lightning-rod man still dwells in the land; still travels in storm-time, and drives a brave trade with the fears of man.

it tell me to put three this is what i got