Help to complete the sentence: Why ... your credit card?

I have a sentence:

Why ______ your credit card?

The answers:

a) don’t use
b) not use
c) not to use
d) not using

Do you have any idea what the correct answer is and why?


The correct answer is “Why not use your credit card?” because it ‘why not + infinitive’ is a commonly pattern. It’s one way the ‘bare infinitive’ can be used.[YSaerTTEW443543]

TOEFL listening discussions: An assistant lecturer talking to a new student[YSaerTTEW443543]

Thank you very much, Mr. Torsten!

Sorry for the interrupting but I wonder whether the structure is the same as Why don’t you…? Thanks

‘Why don’t you’ refers to a specific person while ‘why not…’ can refer to anyone.[YSaerTTEW443543]

TOEIC listening, question-response: How soon can you start working for us?[YSaerTTEW443543]