## **Core Concept**
The development of language skills in children is a significant milestone in pediatric assessment. Telling a story is a complex language skill that involves combining words, sentences, and ideas into a coherent narrative. This skill is often evaluated as part of assessing a child's language development.

## **Why the Correct Answer is Right**
By the age of 3 years, most children have developed sufficient language skills to start combining sentences and can share simple stories or experiences. This age marks a significant period in language development where children begin to use more complex sentences and can narrate short events or stories with understandable coherence.

## **Why Each Wrong Option is Incorrect**
- **Option A:** Typically, by 2 years, children start using short sentences and may begin to show an ability to combine two ideas, but their storytelling abilities are usually very rudimentary.
- **Option B:** At 4 years, children often have more advanced storytelling abilities, including using descriptive language and more complex narratives. However, the question seems to seek the earliest age by which this skill is generally expected to emerge.
- **Option D:** By 5 years, children's storytelling abilities are usually quite advanced, with the ability to create more detailed and coherent narratives. This option represents an age by which most children would have surpassed the basic skill of telling a story.

## **Clinical Pearl / High-Yield Fact**
A useful clinical pearl is that by 3 years of age, children are expected to have a vocabulary of around 1,000 words and start combining three or more words in a sentence. They should also begin to show an understanding of basic grammar and start to tell simple stories. Pediatricians and developmental specialists often use these milestones to assess language development.

## **Correct Answer:** C. 3 years.