**Core Concept**
A community health centre (CHC) is a type of primary healthcare facility in India, designed to provide comprehensive healthcare services to a specific population. The population covered by a CHC is typically rural or semi-urban, and its catchment area is defined by the government's health infrastructure planning.

**Why the Correct Answer is Right**
A CHC is designed to serve a population of approximately 100,000 people, which is equivalent to 20,000 families. This population size is based on the assumption that a CHC can provide adequate healthcare services, including curative, preventive, and rehabilitative care, to the residents within its catchment area. The CHC is equipped with a team of healthcare professionals, including doctors, nurses, and paramedics, who work together to provide comprehensive healthcare services to the population.

**Why Each Wrong Option is Incorrect**
**Option A:** 5000 is too small a population for a CHC, which would be better suited for a subcentre or primary health centre.
**Option B:** 30,000 is still below the recommended population size for a CHC, and would likely require additional facilities to provide adequate healthcare services.
**Option D:** "None" is incorrect because a CHC is specifically designed to serve a population of 100,000.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that the population size covered by a CHC is based on the government's health infrastructure planning, and can vary depending on the region and availability of resources.

**✓ Correct Answer: C. 100,000**