**Core Concept**
The management of hematoma involves a careful consideration of the patient's clinical status, the size and location of the hematoma, and the potential risks and benefits of surgical intervention. In many cases, hematoma may be managed conservatively, avoiding surgical intervention to prevent complications such as infection, scarring, and nerve damage.

**Why the Correct Answer is Right**
Option C suggests that hematoma must be operated, which is not always the case. Surgical intervention is usually reserved for cases where the hematoma is large, causing significant mass effect, or where there is a risk of complications such as infection or nerve damage. In many cases, hematoma can be managed conservatively, with close monitoring of the patient's clinical status and the hematoma's size. This approach allows for the avoidance of unnecessary surgical risks and complications.

**Why Each Wrong Option is Incorrect**
**Option A:** MRI may be useful in diagnosing and characterizing hematoma, particularly in cases where the diagnosis is uncertain or where there are concerns about the presence of underlying conditions such as aneurysm or arteriovenous malformation. However, MRI is not always necessary to access the hematoma.

**Option B:** The Glasgow Coma Scale (GCS) is a widely used assessment tool for evaluating the level of consciousness in patients with traumatic brain injury. The GCS can provide valuable information about the patient's prognosis, including the risk of mortality and the likelihood of functional recovery. Therefore, GCS assessment can indeed help in prognosis.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that not all hematomas require surgical intervention. A careful evaluation of the patient's clinical status, the size and location of the hematoma, and the potential risks and benefits of surgical intervention is crucial in determining the most appropriate course of management.

**Correct Answer Line**
✓ Correct Answer: C. Haematoma must be operated.