Which sentence uses a contraction or possessive form incorrectly?

A.
I'll hang my poster on their door.

B.
Ella and Rob are still working on they're poster.

C.
I think it's the best poster in its category.

D.
We're hoping to have ours ready soon.

Question

Which sentence uses a contraction or possessive form incorrectly?	
 
 A.
I'll hang my poster on their door.
 
 B.
Ella and Rob are still working on they're poster.
 
 C.
I think it's the best poster in its category.
 
 D.
We're hoping to have ours ready soon.

foreverjennnicole · Answer

B. "They're" means "they are". Which there their or they're means ownership?