Can someone please check if I got this multiple choice friction question right? 9th grade honors Question

Which of the following is not an example of charging by friction?
a. sliding over a plastic-covered car seat
b. scraping food from a metal bowl with a metal spoon
c.walking across a woolen carpet
d. brushing dry hair with a plastic comb

I PICKED LETTER C! IS IT RIGHT? THANKS!

It would be C because the your feet don't (usually) slide against the carpet when you walk, and in all the other options the objects slide against each other, which is what friction is. Good job :)

I would have picked A, but you'll find out when you get the test back, love(:

It's really about static electricity, B won't charge either if they are like metals the other 3 will/can.

I think the answer is A, sliding over a plastic covered car seat.

I would have said B because when you walk on carpets sometimes your get static