A shadow is a surface light cannot touch or reflect off of. Usually shadows appear when the main object is covering a light source. For example, lunar eclipses. Lunar eclipses cause a shadow over Earth because they block the main light source, The Sun from our point of view, casting a giant shadow over Earth.
The correct answer is A. maintaining homeostasis.
Homeostasis is a term referring to an organisms continuous process of maintaining and auto-regulating the conditions of its internal environment. Variables such as pH, temperature, and fluid balance need to be at optimal conditions in order for the organism to function properly.
In this example, the phosphate buffer system permits the organisms to maintain a constant pH in their intracellular fluid. This is one of the organism's homeostatic mechanisms.
The answer would be d because the genes come the two parents
