when a vapor condenses into a liquid?

Question

A) its temperature deacreases
B)its temperature increases
C)it absorbs heat
D)It gives off heat

Answer 1

D, condensation is isothermal


edit: note, to the people posting below, and the asker

giving off heat does not always bring decreasing temperature

if you knew any thermodynamics, a phase transformation, is this case, vapour to liquid, is an isothermal process

Answer 2

A and D, it's cooling off by giving off heat (D), thus losing temperature (A), although it could just be D if it's being compressed into liquid rather than cooled into it.

See the Wikipedia link below. The process is actually exothermic.

Answer 3

when its temperature deacreases(that means it gives off heat); when its pressure increases(therefore volume decreases);and by these process molecules of the vapour come closer to form liquid.