To solve this question, the user needs to know the meaning of the given phrase and the context in which it is used. The phrase "blew the whistle" means to expose or report illegal or unethical behavior.

Now, let's go through each option and explain why it is right or wrong:

A. show: This option is incorrect because the phrase is "blew the whistle," not "showed the whistle." The word "show" does not convey the same meaning as "blew the whistle" in the given context.

B. flute: This option is incorrect because the word "flute" does not fit the given phrase's context. The phrase "blew the whistle" is an idiomatic expression that does not involve an actual whistle.

C. whistle: This option is correct. In the given context, the phrase "blew the whistle" means to report illegal or unethical behavior. The word "whistle" is closely associated with the idiom "blew the whistle" and fits the context correctly.

D. wind: This option is incorrect because the word "wind" does not fit the given phrase's context. The phrase "blew the whistle" is an idiomatic expression that does not involve blowing wind.

Therefore, The Answer is: C