**Core Concept:**
Morbidity refers to the presence of a disease or health condition that affects an individual or a group of individuals, leading to suffering, disability, or death. In epidemiology, true morbidity is calculated as the proportion of a population that is affected by a certain condition or disease. This calculation helps to understand the burden of diseases in a population and guide healthcare policies and interventions.

**Why the Correct Answer is Right:**
The correct answer is D - **True Morbidity = Number of cases / Total Population x 100**. This formula is used to calculate the true morbidity rate of a population by considering the number of individuals with a specific disease or condition, divided by the total population size, and then multiplying by 100 to express the result as a percentage. This helps to understand the prevalence of the condition within the population and enables healthcare professionals and policymakers to make informed decisions regarding healthcare resources allocation and disease prevention strategies.

**Why Each Wrong Option is Incorrect:**
A - **False Morbidity**: False morbidity refers to the prevalence of a condition or disease within a population based on self-reported symptoms or diagnoses. This does not consider the actual number of cases and can lead to an overestimation of the burden of disease in a population.

B - **Mortality**: Mortality refers to the death rates within a population. While mortality data is important for public health purposes, it does not provide information about the actual number of individuals suffering from a disease, hence not the true representation of morbidity.

C - **Prevalence**: Prevalence refers to the number of cases of a disease or condition at a specific point in time. While prevalence is a key metric in epidemiology, it does not indicate the actual number of individuals suffering from the condition, thus not giving a clear picture of morbidity.

**Clinical Pearls:**
1. True morbidity provides a more accurate representation of the burden of disease in a population, which is essential for healthcare planning and resource allocation.
2. Understanding morbidity allows for identification of health issues within a population, enabling targeted interventions and public health measures to improve health outcomes.
3. Incorrectly selecting any of the wrong options (mortality, prevalence) can lead to misleading conclusions regarding the burden of diseases in a population, making true morbidity calculation essential for informed decision-making in public health and healthcare planning.