## **Core Concept**
The protein content in cow's milk can vary slightly depending on factors like the breed of cow and diet, but a commonly cited average value is around 3.2 grams of protein per 100 milliliters. This value encompasses both casein and whey proteins, which are the primary protein components in milk.

## **Why the Correct Answer is Right**
Cow's milk contains approximately 3.2 grams of protein per 100 milliliters, which is a well-established nutritional fact. This protein is crucial for growth and development, especially in infants and young children. The proteins in milk are of high quality, meaning they contain all essential amino acids necessary for human health.

## **Why Each Wrong Option is Incorrect**
- **Option A:** This option suggests a significantly lower protein content than what is typically found in cow's milk. Without a specific value, it's hard to directly refute, but given that cow's milk is known to have around 3.2 grams of protein per 100 ml, any value substantially lower than this would be incorrect.
- **Option B:** Similarly, this option implies a different protein content, but without specifics, we know that cow's milk averages around 3.2 grams per 100 ml, making any significantly different value incorrect.
- **Option D:** This option suggests a higher protein content. While there can be variations based on the factors mentioned, 3.2 grams per 100 ml is a commonly cited average, making significantly higher values less likely to be correct for typical cow's milk.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that cow's milk is often used as a source of dietary protein, and its protein content is considered of high biological value due to its complete amino acid profile. This makes it particularly beneficial for growth and repair.

## **Correct Answer:** C. 3.2 gm.