**Core Concept**
Dengue fever is a mosquito-borne viral disease caused by four distinct serotypes of the dengue virus (DENV 1-4), primarily transmitted by the Aedes aegypti mosquito. The disease is characterized by a flu-like illness, which can progress to severe dengue, a potentially life-threatening condition.

**Why the Correct Answer is Right**
- Option **c** is correct because severe myalgia is a hallmark symptom of dengue fever, leading to the colloquial designation "break-bone fever." This symptom is due to the viral replication in muscle tissues and the subsequent activation of the immune response.
- Option **e** is correct as epistaxis (nosebleeds) and scattered petechiae (small spots due to blood leakage) are features of complicated dengue, which can occur due to vascular leakage and thrombocytopenia.
- All the other options are incorrect.

**Why Each Wrong Option is Incorrect**
**Option a:** All four distinct dengue viruses do not have Aedes aegypti as their principal vector; Aedes albopictus is also a significant vector for dengue virus transmission.
**Option b:** Aedes aegypti primarily bites during the day, but they can also bite at night, especially in areas with low light conditions. They usually inhabit dwellings and surrounding areas.
**Option d:** Macular rash, adenopathy, palatal vesicles, and scleral injection are not typical features of dengue fever. While some patients may present with a maculopapular rash, these specific features are not characteristic of the disease.

**Clinical Pearl / High-Yield Fact**
Dengue fever can be prevented by eliminating breeding sites of the Aedes mosquito, using insecticide-treated bed nets, and wearing protective clothing. Additionally, early recognition and management of severe dengue are critical to prevent complications and fatalities.

**Correct Answer: C. Severe myalgia that gave rise to the colloquial designation "break-bone fever".**