A person is choking, what happens to their face?\nOptions:\n- cross street\n- suffer pain\n- own object\n- turn blue\n- sweat
Please answer the following question by reasoning step-by-step.
turn blue
When people are choking, they cannot breath.

When one cannot breath, the body does not get enough oxygen.

When the body does not get enough oxygen, the face starts to turn blue.

.

Final answer: turn blue