Biological value is maximum in:
**Core Concept**
The biological value (BV) of a protein is a measure of its quality, reflecting the extent to which it is absorbed and utilized by the body for growth and maintenance. It is an indicator of the protein's digestibility and the efficiency of its utilization by the body.
**Why the Correct Answer is Right**
The biological value of a protein is influenced by its amino acid composition, particularly the presence of essential amino acids. Whey protein is a complete protein that contains all essential amino acids in a ratio that closely matches the body's requirements. As a result, it has a high biological value, making it an excellent source of protein for muscle growth and repair. The high BV of whey protein is due to its excellent digestibility and the presence of branched-chain amino acids (BCAAs), which are particularly important for muscle protein synthesis.
**Why Each Wrong Option is Incorrect**
**Option A:** While casein protein is also a complete protein, its BV is lower than that of whey protein due to its slower digestion rate, which can lead to a more gradual but less intense increase in muscle protein synthesis.
**Option B:** Soy protein is a high-quality protein that contains all essential amino acids, but its BV is lower than that of whey protein due to the presence of trypsin inhibitors, which can impair protein digestion and absorption.
**Option C:** Egg protein is a complete protein with a high BV, but it is not as high as that of whey protein due to the presence of sulfur-containing amino acids, which can be limiting in some individuals.
**Clinical Pearl / High-Yield Fact**
Whey protein is often used as a supplement by athletes and individuals engaged in resistance training due to its high BV and ability to stimulate muscle protein synthesis.
**Correct Answer:** C. Whey protein has the maximum biological value among the options listed.