**Core Concept**
The question pertains to the essential mineral requirements for children, specifically the daily potassium intake necessary for optimal growth and development. Potassium is a crucial electrolyte involved in various bodily functions, including nerve impulse transmission, muscle contraction, and maintaining fluid balance.

**Why the Correct Answer is Right**
The recommended daily intake of potassium varies based on age, sex, and weight. The World Health Organization (WHO) and the National Academy of Sciences (NAS) provide guidelines for potassium intake in children. For children aged 1-3 years, the recommended daily intake is approximately 1.2 grams of potassium. This requirement is essential for maintaining proper muscle and nerve function, as well as supporting overall health.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is not a valid unit of measurement for potassium intake.
**Option B:** This option is a unit of measurement, but it is not relevant to the required daily potassium intake in children.
**Option C:** This option is a lower value than the recommended daily intake for children aged 1-3 years.

**Clinical Pearl / High-Yield Fact**
It's essential to note that excessive potassium intake can lead to hyperkalemia, a condition characterized by elevated potassium levels in the blood, which can be life-threatening.

**Correct Answer:** D. 1.2 grams