## Core Concept
The question pertains to the growth and development of facial features, specifically lip thickness, in males. It involves understanding the changes that occur during puberty and adolescence.

## Why the Correct Answer is Right
Lip thickness, like other facial features, changes during growth and development. Research indicates that facial features, including lip thickness, tend to reach their maximum growth and development at specific ages. For males, lip thickness is known to reach its maximum around the age of 20-25 years, as part of the overall growth and maturation process.

## Why Each Wrong Option is Incorrect
- **Option A:** This option suggests an age that is too early for maximum lip thickness development in males. Lip thickness continues to develop beyond this age.
- **Option B:** This option might seem plausible but is not the correct age for maximum lip thickness in males.
- **Option D:** This option suggests an age that might be considered late for the maximum development of lip thickness in males.

## Clinical Pearl / High-Yield Fact
A key point to remember is that facial growth and development, including lip thickness, continue into the early twenties in males. This is an important consideration in plastic surgery, orthodontics, and forensic anthropology.

## Correct Answer: C. 20-25 years.