Find out the correct sentence:

A She is sleeping for six hours

B She has been sleeping for six hours

C She is sleeping since six hours

D She has been sleeping since six hours.

Correct Answer: Option B

অনির্দিষ্ট সময় থেকে চলতে থাকলে সময়ের পূর্বে for আর বাক্যটি present perfect continuous tense -এ হয় ।