The role of a medical assistant came about because of 1) a growing industry 2) a lack of nurses 3) larger hospitals 4) all of the above

all of the above

Explanation:

This is because the industry was growing but there wasnt much employment and hospitals were running low on the need of staff but hospitals were growing and getting bigger which meant more support was needed to help treat patients

answer(b) keep oxygenated and deoxygenated blood separate;