You are writing an essay on whether or not running barefoot is harmful to a runner's health, and you need to cite an effective quotation.

which quotation from a research source could you use in your essay?

a) "running is endemic to humankind's nature and exhibits humans at their most natural; we were born to run."

b) "some famous runners throughout history have been michael johnson, steven prefontaine, and roger bannister."

c) "there are many forms of exercise that can keep a person healthy: walking, lifting weights, or running."

d) "unsurprisingly, many running shoe companies have begun paying for research into ways running barefoot damages a runner's feet."