**Core Concept**
Exudative retinal detachment occurs due to the accumulation of fluid beneath the retina, often resulting from inflammation, vascular permeability, or neoplastic processes. This type of detachment is characterized by the presence of subretinal fluid without a retinal break. **Retinal pigment epithelium** and **choroidal** diseases can contribute to its development.

**Why the Correct Answer is Right**
The correct answer includes conditions that lead to exudation of fluid beneath the retina. **Toxaemia of pregnancy**, also known as preeclampsia or eclampsia, can cause **vascular permeability** increases, leading to fluid accumulation. **Central serous retinopathy** is characterized by the accumulation of fluid under the retina due to a **leak** in the **retinal pigment epithelium**. **Scleritis** and **dysthyroid eye disease** can also lead to inflammation, increasing vascular permeability.

**Why Each Wrong Option is Incorrect**
**Option A:** Scleritis can cause exudative detachment but is not the only cause.
**Option C:** Dysthyroid eye disease can lead to exudation.
**Option E:** Sickle cell retinopathy typically causes non-exudative detachments due to **retinal ischemia** and **neovascularization**.

**Clinical Pearl / High-Yield Fact**
Remember that exudative retinal detachments often have a distinct appearance on **fluorescein angiography**, showing leakage of dye into the subretinal space.

**Correct Answer: D. Central serous retinopathy**