by making the comb more absorbent by giving the comb an electrical charge by increasing the thermal energy of the comb by breaking some of the chemical bonds in the comb
I gave my students this multiple choice question: Greta passed a comb through her hair several times. She then placed the comb next to a stream of water flowing from a faucet. Greta observed the stream of water bend toward the comb. How did passing a comb through her hair allow the comb to bend the stream of water?

Only one answer is correct among these 4 choices:
- by making the comb more absorbent
- by giving the comb an electrical charge
- by increasing the thermal energy of the comb
- by breaking some of the chemical bonds in the comb

Could you tell me which one is correct?

by giving the comb an electrical charge