The correct answer is option B, that is, all living organisms are composed of one or more cells, which came from pre-existing cells.
A scientific theory refers to a well-substantiated illustration of some characteristic of the natural world, on the basis of a number of facts, which have been repeatedly confirmed via the experiment and observation. Such fact-supported theories are not hypotheses, however, are reliable explanations of the real world.
During the late 1830s, the zoologist Schwann and the botanist Schleiden were examining tissues and postulated the unified cell theory. According to the unified cell theory, all the living things comprises of one or more cells, the cell is the fundamental unit of life, and the new cells originate from the pre-existing cells.
B. Gray squirrels
because in the food chain a primary consumer is an animal that feeds on plants; a herbivore.
<span>Lymph nodes are abundant organs comprising a major part of the lymphatic system, and can indeed be found throughout the body, connected by the lymphatic vessels. However, the highest concentration of clustering occurs within in the inguinal region, cervical region, and axillary region.</span>