Mark the letter A, B, C, or D on your answer sheet to indicate the cor

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.    

Mom, it isn’t safe to go on vacation at present, ___?

• A. A. did it
• B. B. was it
• C. C. is it
• D. D. does it

câu chính ở dạng phủ định => tag question ở dạng khẳng định
=> C