Final answer:
Osmotic diarrhea is the form of diarrhea caused by a lactase deficiency.
Step-by-step explanation:
The form of diarrhea caused by a lactase deficiency is osmotic diarrhea.
Lactose intolerance is a condition where the small intestine does not produce enough lactase, the enzyme that digests lactose. When lactose is not properly digested, it can cause an osmotic imbalance in the intestines, leading to osmotic diarrhea.
For example: When someone with lactose intolerance consumes dairy products, the undigested lactose in the intestines attracts water, causing an increase in osmotic pressure and resulting in diarrhea.