According to Hagitt&;s classification, a polyp invading neck in between head and stalk is level:

**Core Concept**
Hagitt's classification is a system used to classify the levels of invasion of colorectal polyps, specifically in relation to their relationship with the muscularis mucosae. This classification is crucial for determining the risk of malignancy and the appropriate treatment plan for these polyps.

**Why the Correct Answer is Right**
Hagitt's classification categorizes polyp invasion into four levels:

- Level 0: Polyps that do not penetrate the muscularis mucosae.
- Level 1: Polyps that invade into the submucosa but do not reach the muscularis mucosae.
- Level 2: Polyps that invade the muscularis mucosae.
- Level 3: Polyps that invade through the muscularis mucosae but do not reach the subserosa.
- Level 4: Polyps that invade through the subserosa.

In the context of a polyp invading the neck between the head and stalk, it is considered a level **3** polyp because the polyp has invaded through the muscularis mucosae but has not reached the subserosa.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not specify a level of invasion according to Hagitt's classification.
**Option B:** This option is incorrect because it does not accurately describe the level of invasion for a polyp in the neck between the head and stalk.
**Option C:** This option is incorrect because it does not accurately describe the level of invasion for a polyp in the neck between the head and stalk.

**Clinical Pearl / High-Yield Fact**
It is essential to remember that Hagitt's classification is used to determine the risk of malignancy in colorectal polyps. Polyps with a higher level of invasion according to Hagitt's classification have a higher risk of containing cancer cells.

**Correct Answer: C. Level 3.**