**Core Concept**
Vitreous hemorrhage is a condition characterized by the accumulation of blood in the vitreous gel of the eye, often resulting from retinal tears, diabetic retinopathy, or trauma. The investigation of choice for vitreous hemorrhage should be able to visualize the posterior segment of the eye and assess the extent of hemorrhage.

**Why the Correct Answer is Right**
The ultrasound biomicroscopy (UBM) is a non-invasive imaging modality that uses high-frequency sound waves to produce high-resolution images of the posterior segment of the eye. It is particularly useful in visualizing vitreous hemorrhage, as it can penetrate the blood and provide detailed images of the retina and choroid. The UBM is also useful in evaluating the extent of hemorrhage and in guiding further management.

**Why Each Wrong Option is Incorrect**
**Option A:** Computed Tomography (CT) scan is not the investigation of choice for vitreous hemorrhage, as it may not be able to penetrate the blood and provide detailed images of the posterior segment of the eye.
**Option B:** Magnetic Resonance Imaging (MRI) is not typically used to evaluate vitreous hemorrhage, as it may not provide sufficient resolution of the posterior segment of the eye.
**Option C:** Fluorescein angiography is a useful tool in evaluating diabetic retinopathy, but it is not the investigation of choice for vitreous hemorrhage, as it may not provide detailed images of the extent of hemorrhage.

**Clinical Pearl / High-Yield Fact**
Mnemonic: "VITREOUS" - Vascular (diabetic retinopathy), Inflammation (uveitis), Trauma, Retinal tears, Endophthalmitis (infection), Uveitis (inflammation of the uvea), Surgery (post-operative complications).

**Correct Answer:** C. Ultrasound Biomicroscopy (UBM).