Answered

Which pronoun correctly completes the sentence?

__________ performing a special song for your birthday.



A.
They're


B.
Their


C.
There


D.
Theirs



Answer :

Kattay
Let's do the process of elimination, A seems to make sense with the context, B, not exactly, C, definitely not, and D, not exactly workin', so A is the best answer, hope this helps
A is the answer  and its pronoun perfect too :D