In my opinion, i think it's D but im not sure. Hope this helped, have an amazing day :)
You will gain more health benefits because your training the muscles to be under stress.
Answer:unconditioned stimuli
Pavlov fed dogs and was looking at salivation in response to the food.
At a certain point, whenever he entered the
room, the dog would start to salivate even when he was not bringing them
food. The exact same happened to Dionne when she saw the chili peppers even though it was just a picture and not the real thing.
This it is an unconditioned response to an unconditioned
stimulus.
I believe it’s carbon dioxide, because you use your respiratory system to breathe in oxygen, and oxygen goes through your circulatory system. And you breathe out CO2.
