**Core Concept**
The question is testing the student's knowledge of the characteristic findings in carcinoma of the esophagus, which is a type of malignancy that affects the esophagus. This concept is related to the pathophysiology of esophageal cancer and its impact on the surrounding tissues and structures.

**Why the Correct Answer is Right**
Carcinoma of the esophagus often leads to the narrowing of the esophageal lumen, which is known as esophageal stricture. This occurs due to the infiltration and destruction of the normal esophageal tissue by the cancer cells. As a result, the normal passage of food through the esophagus is impeded, leading to symptoms such as dysphagia (difficulty swallowing). The stricture can be visualized on endoscopy as a narrowing of the esophageal lumen.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is not relevant to the characteristic findings in carcinoma of the esophagus. While some cancers may cause obstruction, this is not a specific characteristic of esophageal cancer.
**Option B:** This option is incorrect because it does not accurately describe a common finding in carcinoma of the esophagus. While some cancers may cause pain or discomfort, this is not a specific characteristic of esophageal cancer.
**Option C:** This option is incorrect because it does not accurately describe a common finding in carcinoma of the esophagus. While some cancers may cause bleeding, this is not a specific characteristic of esophageal cancer.

**Clinical Pearl / High-Yield Fact**
A key point to remember is that carcinoma of the esophagus often presents with symptoms of dysphagia, which can progress from difficulty swallowing solids to difficulty swallowing liquids. This progression is a classic clinical correlation that should be remembered for exam purposes.

**Correct Answer: C. Esophageal stricture.**