The reason that the steroid hormone aldosterone affects only a small number of cells in the body is that
A) it is unable to enter nontarget cells.
B) nontarget cells convert aldosterone to a hormone to which they do respond.
C) only its target cells contain aldosterone receptors.
D) nontarget cells destroy aldosterone before it can produce any effect.
E) only its target cells get exposed to aldosterone
Answer: C