**Core Concept**
Measles is a highly contagious viral infection caused by the measles virus (MV), which spreads through respiratory droplets. The epidemiological determinants of measles refer to the factors that influence its transmission and spread within a population.

**Why the Correct Answer is Right**
The correct answer is related to the concept of herd immunity. Herd immunity is a phenomenon where a significant portion of a population becomes immune to a disease, thereby protecting those who are not immune, such as young children or immunocompromised individuals. For measles, herd immunity is achieved when at least 93-95% of the population is vaccinated. This is because measles is highly contagious and spreads quickly in areas with low vaccination rates.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because measles is not a vector-borne disease, which means it is not transmitted by vectors like mosquitoes or ticks.
**Option B:** This option is incorrect because the primary mode of transmission for measles is respiratory droplets, not fecal-oral contamination.
**Option C:** This option is incorrect because the basic reproduction number (R0) of measles is estimated to be around 12-18, which means a single infected individual can infect 12-18 others in a completely susceptible population.

**Clinical Pearl / High-Yield Fact**
A key concept in measles epidemiology is the "critical vaccination coverage threshold," which is the percentage of the population that needs to be vaccinated to prevent outbreaks. For measles, this threshold is estimated to be around 93-95%.

**Correct Answer: C.**