Theobromine toxicity affects various organ systems in a dose-dependent fashion. Which of the following is the correct representation of organ systems that will be affected at low doses, moderate doses, and high doses, respectfully?
a. gastrointestinal, CNS, hepatic.
b. gastrointestinal, renal, cardiovascular.
c. CNS, renal, gastrointestinal.
d. gastrointestinal, cardiovascular, CNS.