## Core Concept
The question assesses the developmental milestones of an eight-month-old child, focusing on motor skills and physical abilities. At this age, infants typically achieve certain gross motor skills, such as sitting without support, crawling, and possibly standing with support.

## Why the Correct Answer is Right
Option is likely related to sitting without support, which is a developmental milestone typically achieved around 6-7 months of age. By eight months, most infants can not only sit without support but also have improved their balance and may be attempting to stand or move while holding onto furniture. This option likely aligns with sitting up or a similar foundational motor skill.

## Why Each Wrong Option is Incorrect
- **Option A:** If option A refers to a skill that is typically mastered later than 8 months, such as walking independently (usually around 12 months), it would be incorrect.
- **Option B:** If option B describes a skill not yet achieved by most 8-month-old infants, such as standing without support or speaking a few words to communicate, it would be incorrect.
- **Option D:** If option D suggests a skill that is beyond the typical range for an 8-month-old, such as running or saying short sentences, it would be incorrect.

## Clinical Pearl / High-Yield Fact
A key developmental milestone for an 8-month-old child is the ability to **sit up without support** and **crawl**. Clinicians often use these milestones to assess neurological development. Remember, "S" is for sitting and standing (with support) around this age.

## Correct Answer: C.