**Core Concept**
The earliest change in the intestine in Crohn's disease is related to the immune system's response to luminal antigens, leading to an inappropriate inflammatory reaction. This involves the activation of immune cells, including T lymphocytes, and the release of pro-inflammatory cytokines.

**Why the Correct Answer is Right**
The correct answer is related to the concept of "ulceration" in Crohn's disease. The earliest change in the intestine is the development of ulcers, which are a result of the immune system's inappropriate response to luminal antigens. This leads to the release of pro-inflammatory cytokines, such as TNF-alpha, which cause tissue damage and ulceration. The ulcers are often deep and linear, and can lead to complications such as narrowing of the intestine (strictures) and fistulae.

**Why Each Wrong Option is Incorrect**
**Option A:** "Inflammation" is a general term that can occur in many conditions, but it is not specific to Crohn's disease. Inflammation is a common feature of many gastrointestinal conditions, including irritable bowel syndrome (IBS) and ulcerative colitis (UC).

**Option B:** "Crypt abscesses" are a feature of ulcerative colitis (UC), not Crohn's disease. Crypt abscesses are collections of neutrophils in the crypts of Lieberkühn, and are a hallmark of UC.

**Option C:** "Fibrosis" is a late complication of Crohn's disease, which occurs as a result of chronic inflammation and scarring. While fibrosis can occur in Crohn's disease, it is not the earliest change.

**Clinical Pearl / High-Yield Fact**
The "skip lesions" of Crohn's disease are characteristic of the disease, and occur when areas of normal intestine are interspersed with areas of diseased intestine. This can lead to difficulties in diagnosis, as the disease may not be uniformly distributed throughout the intestine.

**Correct Answer: B. Crypt abscesses are not the earliest change in Crohn's disease.