**Core Concept**
Diverticulitis is a condition characterized by inflammation of the diverticula, which are small pouches or sacs that protrude from the wall of the colon. The condition typically affects older adults, although it can occur at any age.

**Why the Correct Answer is Right**
Diverticulitis is often associated with an increased risk of complications, such as abscess formation, perforation, and peritonitis. Younger patients with diverticulitis may be more likely to have a more aggressive disease course due to their overall health and immune status. This is because younger individuals are more likely to have a higher level of physical activity, which can contribute to the severity of symptoms. Additionally, younger patients may be less likely to have comorbid conditions that could influence the disease course.

**Why Each Wrong Option is Incorrect**
**Option A:** Diverticulitis is less common in younger individuals, and when it does occur, it tends to be less severe. This option is incorrect as diverticulitis is not typically seen in young patients.
**Option B:** Diverticulitis is not usually an incidental finding at operation. The condition typically presents with symptoms such as abdominal pain, fever, and changes in bowel habits. This option is incorrect as diverticulitis is often symptomatic.
**Option D:** Left-sided colon involvement is not more common than right-sided involvement. Diverticulitis can occur in any part of the colon, but it is more common on the left side. This option is incorrect as it implies a higher prevalence on the left side, which is not the case.
**Option E:** Operation is not always necessary for all patients with diverticulitis. While surgery may be required in some cases, many patients can be managed conservatively with antibiotics and supportive care. This option is incorrect as it implies that surgery is never an option.

**Clinical Pearl / High-Yield Fact**
Diverticulitis is more common in older adults, and younger patients with the condition may be more likely to have a more aggressive disease course. It's essential to consider the patient's age and overall health when managing diverticulitis.

**Correct Answer: C. Young patients have more aggressive disease**