Ans. B. 4DiarrheaDefinition-It is defined according to symptoms as increase in liquidity, frequency and volume of stools; and according to sign as increase in stool weight of more than 200gm/day.Pseudo diarrhea-it is the frequent passage of small volume of stools. It is seen in irritable bowel syndrome and proctitis.Classification-It is classified according to duration asa. Acute-Duration less than 2 weeks.b. Persistent-Duration of 2-4 weeks.c. Chronic-Duration of more than 4 weeks.