Which sentence uses possessive personal pronouns correctly?

a. Alicia thought that the blue jacket was her's.

b. The dolphin bobbed it's head up and down.

c. Your's was the one with the blue tag, on the table.

d. Did you eat the whole potato and its skin?

The sentence which uses possessive personal pronouns correctly is sentence (d). Did you eat the whole potato and its skin?

the rest of the sentences should've been written like this:

Alicia thought that the blue jacket was hers.

The dolphin bobbed its head up and down.

Yours was the one with the blue tag, on the table.