This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Gastrointestinal tract, Subject name: Pharmacology
Bisacodyl is: 
Select and explain. 
A. Bulk forming, B. Stool softner, C. Stimulant purgative, D. Osmotic purgative
C: Stimulant purgative
Answer: C: Stimulant purgative 
Explanation: stimulant purgatives 1.diphenylmethane( bisacodyl,sodium picosulfate) 2. Anthraquinones(senna) 3.5HT4 antagonisr(prucalopride) 4.fixed oil(castor oil) ESSENTIALS OF MEDICAL PHARMACOLOGY SEVENTH EDITION KD TRIPATHI PG NO .672