The period when an embryo of a seed is alive but no longer growing is considered to be in it's dormant stage. During dormancy, they seed is restricted from growing due to environmental conditions such as limited sunlight, water or unfavorable temperatures.
In mammals urine is expelled through the urethra which is part of the excretory system in unicellular organisms waste products are discharged directly through the surface of the cell
Your answer should be A. by observing the formation of sedimentary rocks.