There is a lack of information to answer the question..
Mitochondria create energy and the more energy a being needs, the more mitochondria or the bigger the mitochondria
Bottle, pampers, binky (pacifier), milk
The right option is a. variations.
Variations are the differences between the individual organisms of the same species which is as a result of genetic differences or the influence of environmental factors on the expression of the genetic abilities. Variation may be expressed in behavior, physical appearance, learning, and metabolism. The two types of variations are somatic variation and germinal variation.
