Correct the given sentence gramatically.

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

Improve the bracketed part of the sentence.
The (reason of) her outburst in the party is yet unknown.

In the following question, out of the four alternatives, select the alternative which best expresses the meaning of the idiom/Phrase.
To accept the gauntlet

In the following question, out of the four alternatives, select the alternative which best expresses the meaning of the idiom/Phrase.
The thin end of the wedge

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

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

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

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

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.
The meeting was presided _____ by the Chairman.