[Question deleted because it is from a banned source. Please read (and follow!) the guidelines before you post.]
Can you explain why the answer is C instead of B?

B is redundant: 'share' and 'same' don't belong in the same construction.

If your name is Jimmy and my name is Jimmy, then I don't 'share the same first name with you'; I share a/my first name with you. Alternatively, I have the same first name as do you.

You'll hear things like 'We share the same house' a lot, but they fall under the umbrella of informal usage.

Hi Ron ,

because many residents of the Southeast do not have the same ethnic heritage as Northeasterners DO

shouldn't answer choice C end with DO as above.... ???

Please help..thanks

Hey, guys - sorry, but this is from a banned source (this source illegally uses copyrighted material for which it does not have permission). :(