True regarding Ca colon is –
**Core Concept**
The question is testing knowledge about the characteristics of colorectal cancer (Ca colon), a type of cancer that arises from the epithelial lining of the colon or rectum. Colorectal cancer is a common malignancy worldwide, often associated with genetic predisposition, dietary factors, and environmental exposures.
**Why the Correct Answer is Right**
The correct answer is related to the molecular mechanisms underlying colorectal carcinogenesis. Colorectal cancer is characterized by the accumulation of genetic mutations in key oncogenes and tumor suppressor genes. The most common genetic alterations involve the APC gene, which is a tumor suppressor gene that regulates the Wnt/β-catenin signaling pathway. Mutations in the APC gene lead to the accumulation of β-catenin in the nucleus, where it acts as a transcription factor to promote cell proliferation and survival.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it does not specify a relevant characteristic of colorectal cancer.
* **Option B:** This option is incorrect because it is not a true statement about colorectal cancer.
* **Option C:** This option is incorrect because it is not a well-established risk factor for colorectal cancer.
**Clinical Pearl / High-Yield Fact**
A key risk factor for colorectal cancer is a family history of the disease, particularly in individuals with a first-degree relative diagnosed with colorectal cancer before the age of 50. This is often associated with Lynch syndrome, an inherited condition caused by mutations in DNA mismatch repair genes.
**Correct Answer:** C.