**Core Concept**
Water absorption from the gastrointestinal tract (GIT) is a crucial process that occurs mainly in the small intestine, with some absorption also taking place in the large intestine. The order of water absorption is determined by the presence of specific transport mechanisms and the composition of the intestinal contents.

**Why the Correct Answer is Right**
The order of water absorption from the GIT is duodenum, jejunum, and ileum. Water absorption in the duodenum is primarily facilitated by the presence of sodium and chloride ions, which are absorbed through specific transport mechanisms. As the intestinal contents move into the jejunum, water absorption increases due to the higher concentration of sodium and chloride ions. The ileum is responsible for the final stages of water absorption, with a significant proportion of water being absorbed here due to the presence of specific transport mechanisms, such as the sodium-glucose cotransporter.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because the duodenum is the primary site of water absorption, not the last.
**Option B:** This option is incorrect because water absorption in the large intestine is much less significant compared to the small intestine.
**Option C:** This option is incorrect because the jejunum is the primary site of water absorption after the duodenum, not the ileum.

**Clinical Pearl / High-Yield Fact**
The order of water absorption from the GIT is often remembered using the mnemonic "DUJIE" (duodenum, jejunum, ileum, and large intestine).

**Correct Answer: C. Ileum.**