which one is correct in grammar?

which one is correct in grammar? Which one is correct? which one is correct ?help me! thanks! GMAT question( which one is correct) which sentence is correct? which word is correct which is correct?why? Is this address in China an office. Which is correct which of the following is correct in a Lewis diagram!? That one is correct. who is she? and who is her.which one is correct? tell me why Which sentence is correct?Why?