Research indicates that using electronic devices before bed may make it difficult for people to fall asleep. the light appears to interfere with the body’s ability to create this hormone, which is responsible for sleep and wake cycles.

The answer is C Melatonin  it is the sleep inducing horomone

I remember reading in a research article from last year that talked about this. From the four options presented, c. Melatonin should be correct. Melatonin helps you sleep but the light from devices suppresses this hormone which then affects your day and night cycles.

That’s what i was going to say.

This gel or liquid can be placed under the tongue of an unconscious person. this is important because you should never pour anything down the throat of an unconscious person-- s/he could choke.