Possessive pronouns vs. possessive adjectives

[grisha]

English Grammar Tests, Elementary Level

ESL/EFL Test #101 "Possessive pronouns", question 8

The fluffy brown puppy is ..........

(a) its
(b) my
(c) theirs

English Grammar Tests, Elementary Level

ESL/EFL Test #101 "Possessive pronouns", answer 8

The fluffy brown puppy is theirs.

Correct answer: (c) theirs

Your answer was: incorrect
The fluffy brown puppy is my.
_________________________

Why is it incorrect with my?
It can be also with my.

grisha

[Yankee]

Hi

The only correct answer is "theirs".

You could also say:
- mine (not "me")
- yours
- his
- hers
- ours

But none of these were choices in the test question.

Amy