Which of the following sentences has the usage of 'there', 'their' or 'they're'?

Question

Which of the following sentences has the   usage of 'there', 'their' or 'they're'?

Accepted Answer

Our neighbours have bought a second TV, they're new one is an HD TV.

Answer

There is an old haunted house.

Answer

They're coming over for dinner.

Answer

Their dog is pretty awesome.