Final answer:
The true statement about adrenal parenchymal cells is that those of the adrenal medulla produce epinephrine and norepinephrine, vital for the 'fight-or-flight' response.
Step-by-step explanation:
The statement concerning adrenal parenchymal cells that is true is: B) Those of the adrenal medulla produce epinephrine and norepinephrine. The adrenal medulla is the inner part of the adrenal gland and is responsible for producing catecholamines, which include the hormones epinephrine and norepinephrine. These hormones enable the body to mount a rapid, short-lived 'fight-or-flight' response to stress.
The zona fasciculata, the intermediate region of the adrenal cortex, produces glucocorticoids like cortisol, rather than androgens, hence option A is incorrect. The zona glomerulosa, the most superficial region of the adrenal cortex, produces mineralocorticoids and not glucocorticoids, so option C is incorrect. Finally, regarding option D, while the cortex cells do contain organelles related to steroid hormone synthesis, they are not distinguished primarily by the presence of 'numerous secretory granules', which is more characteristic of the cells in the adrenal medulla that release epinephrine and norepinephrine.