## Core Concept
The eruption of primary teeth, also known as deciduous or baby teeth, typically begins around 6 months of age but can start as early as 3 months or as late as 12 months. By 4 months, it's generally expected that no teeth have erupted, but parents often get concerned about the timeline.

## Why the Correct Answer is Right
Reassurance is a key part of pediatric care, especially for first-time parents who might not be aware of the normal variation in tooth eruption times. At 4 months, the development of teeth is still within the normal range if they haven't erupted yet. The correct approach is to educate and reassure the parents that this is within the normal range and advise them on what to expect and how to manage teething symptoms when they arise.

## Why Each Wrong Option is Incorrect
- **Option A:** This option is not provided, but typically, advising a parent to use a specific remedy or intervention at 4 months without teeth might not be necessary.
- **Option B:** Similarly, this option is not provided, but any option suggesting an immediate intervention or concern might not be warranted at this age.
- **Option D:** Without the specific details of option D, it's hard to assess its accuracy directly, but any option that suggests unnecessary worry or intervention could be considered incorrect.

## Clinical Pearl / High-Yield Fact
A useful point to remember is that the first primary teeth to erupt are usually the lower central incisors, often around 6 months of age. Parents can be reassured that a wide range of eruption times is considered normal, and by 12-14 months, if no teeth have erupted, further evaluation might be warranted.

## Correct Answer: C. Reassure the parents that this is within normal limits.