Correct the given sentence gramatically.

Shreya, who she is my best friend, is a singer.

In the following question, out of the four alternatives, select the alternative which will improve the bracketed part of the sentence. In case no improvement is needed, select "no improvement".

The shoes were very expensive; I couldn't afford (to buying) them.

In the following question, out of the four alternatives, select the alternative which best expresses the meaning of the idiom/phrase.
Best of both worlds

In the following question, out of the four alternatives, select the alternative which best expresses the meaning of the idiom/phrase.
Ball is in your court

In the following question, out of the four alternatives, select the word opposite in meaning to the word given.
Recede

In the following question, out of the four alternatives, select the word opposite in meaning to the word given.
Rebuff

In the following question, out of the four alternatives, select the word similar in meaning to the word given.
Realm

In the following question, out of the four alternatives, select the word similar in meaning to the word given.
Ravine

In the following question, the sentence given with blank to be filled in with an appropriate word. Select the correct alternative out of the four and indicate it by selecting the appropriate option.
______________ to my political rival's statement, the data reveals crime has not increased in this country.