I believe it is the 3rd one but I am not sure but if you want an explanation on why, I will tell you that phobias are based off of a certain object,situations,or anything that makes you react with so much fear. That is why I think it is the 3rd one but let me know what the answer is I am curious of what the actual answer may be.
What task do you what to accomplish?
They Protect Us From Risk
Explanation:
one of the things that you can do can be drinking soemething(like a healthy protein smoothie) with protein powder but also doing like weights or pushups,etc
Difussion occurs from a high concentrated region to a low concentrated region. The velocity of diffussion is proportional to the differential of concentrations. In the lung arrives blood with low levels of oxygen while the long is rich with fresh oxygen so the oxygen flows from the lung tissues to the blood.
The other tissues consume oxygen continually them they get poor in oxygen and so the oxygen that is in the blood diffuses to the tissue that is poor in oxygen.