**Core Concept**
The death rate in a population is calculated as the number of deaths per 1000 population per year. In this scenario, we are given the number of deaths due to cholera and the total population, but we also need to consider the total number of deaths in the population to calculate the overall death rate.

**Why the Correct Answer is Right**
To calculate the death rate, we need to first find the total number of deaths in the population, which is 50 (10 due to cholera and 40 due to other causes). The death rate is then calculated as (total deaths / total population) x 1000. In this case, it is (50 / 5000) x 1000 = 10 deaths per 1000 population.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is not provided, so we skip it.
* **Option B:** This option is also not provided, so we skip it.
* **Option C:** This option is not provided, so we skip it.
* **Option D:** This option is also not provided, so we skip it.

**Clinical Pearl / High-Yield Fact**
Remember that the death rate is a measure of the number of deaths per 1000 population per year, and it can be calculated using the formula: (total deaths / total population) x 1000.

**Correct Answer: D. 10 deaths per 1000 population.**