Which of the following statements is incorrect?

Options

A. Brunner's glands are submucosal.
B. Irregular folds of gastric mucosa rugae.
C. Glisson's capsule is the connective tissue sheath of hepatic lobule.
D. Mesothelium or serosa lies in close proximity to the circular layer of muscularis.

Explanation

To solve the question "Which of the following statements is incorrect?", we will analyze each statement provided in the options step by step.

### Step-by-Step Solution:

1. **Evaluate the First Statement:**
- The statement is: "Brunner's glands are submucosal."
- **Analysis:** Brunner's glands are indeed located in the submucosa of the small intestine. This statement is **correct**.

2. **Evaluate the Second Statement:**
- The statement is: "Irregular folds of gastric mucosa are rugae."
- **Analysis:** The irregular folds in the gastric mucosa are known as rugae, which are present in the stomach. This statement is also **correct**.

3. **Evaluate the Third Statement:**
- The statement is: "Gleason's capsule is the connective tissue sheet of the hepatic lobule."
- **Analysis:** The Glisson's capsule (note the correct spelling) is indeed a connective tissue sheath that surrounds the hepatic lobule in the liver. This statement is **correct**.

4. **Evaluate the Fourth Statement:**
- The statement is: "Mesothelium of serosa lies in close proximity to the circular layer of muscularis."
- **Analysis:** The serosa is the outermost layer of the gastrointestinal tract and is made up of a thin layer of mesothelium. It lies in close proximity to the longitudinal layer of muscularis, not the circular layer. Therefore, this statement is **incorrect**.

### Conclusion:
- After evaluating all statements, the incorrect statement is the fourth one: "Mesothelium of serosa lies in close proximity to the circular layer of muscularis."

### Answer:
The incorrect statement is: **Option 4** - "Mesothelium of serosa lies in close proximity to the circular layer of muscularis."

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