**Core Concept**
Short stature is a condition characterized by a height that is below the expected range for an individual's age and sex. This can be due to various factors, including genetic conditions, hormonal imbalances, or other underlying medical conditions.

**Why the Correct Answer is Right**
The correct answer is based on the definition provided by the World Health Organization (WHO). According to the WHO, short stature is defined as a height below -2 standard deviations (SD) from the mean height for age and sex. This definition is used to identify children who may have growth hormone deficiency or other underlying conditions that require medical attention.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it is too low a cutoff for defining short stature. A height below -3 SD is typically associated with severe growth restriction or other significant health concerns.
**Option B:** This option is incorrect because it is too high a cutoff for defining short stature. A height below the 25th percentile is generally not considered to be short stature.
**Option C:** This option is incorrect because it is a height range that is not commonly used to define short stature. While a height below 1.2 m (4 feet) may be considered short, this option is not the correct answer.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that short stature can be a normal variant in some populations, especially in certain ethnic groups. However, if a child's height is below the expected range for their age and sex, further evaluation by a pediatrician or endocrinologist may be necessary to rule out underlying medical conditions.

**Correct Answer: C.**