## **Core Concept**
The question assesses the developmental milestone of hand use and dexterity in infants, specifically the age at which a child can transfer an object from one hand to another. This is a fine motor skill that is part of the normal developmental progression.

## **Why the Correct Answer is Right**
The ability to transfer a toy or object from one hand to another is an important fine motor skill. Typically, infants develop this ability around 4 to 6 months of age. This skill is indicative of improving hand function and coordination. By 5 months, most infants can smoothly transfer objects between their hands, showcasing enhanced dexterity and cognitive understanding of object permanence.

## **Why Each Wrong Option is Incorrect**
- **Option A:** 2 months is too early for this developmental milestone. At this age, infants are just beginning to discover their hands and might start to hold toys but transferring them from one hand to another is not typically observed.
- **Option B:** 7 months might be a bit late for the first demonstration of this skill, as most infants achieve this by around 5 months.
- **Option D:** 10 months is well beyond the age by which most children can transfer objects between their hands; by this age, they have achieved more advanced fine motor skills.

## **Clinical Pearl / High-Yield Fact**
A key developmental milestone to remember is that by 5 months, infants should be able to transfer toys from one hand to another. Failure to achieve this and other milestones at the expected times can be an indicator of developmental delay, warranting further evaluation.

## **Correct Answer:** . 5 months.