Name the regulatory factor in childbirth

relative humidity, temperature and dew point -- are bound together in the mathematical relationship below. relative humidity changes when temperatures change. because warm air can hold more water vapor than cool air, relative humidity falls when the temperature rises if no moisture is added to the air. so i would say a

is this a psat question, if so do not cheat try your best.

c. live where it’s cold and icy

you can have just about every answer you can think of