Egg has all vitamins except –

**Core Concept**
Vitamins are essential nutrients that the human body cannot synthesize in sufficient amounts and must be obtained from the diet. Eggs are a good source of various vitamins, but they lack a specific vitamin.

**Why the Correct Answer is Right**
Eggs are a rich source of vitamins A, D, E, K, and B vitamins, except for vitamin C. Vitamin C is an essential water-soluble vitamin that plays a crucial role in collagen synthesis, iron absorption, and immune function. Eggs are not a natural source of vitamin C, which is typically obtained from fruits and vegetables.

**Why Each Wrong Option is Incorrect**
**Option A:** Vitamin A is present in eggs, which is essential for vision, immune function, and skin health.
**Option B:** Vitamin D is also found in eggs, particularly in fortified eggs, and is crucial for bone health and calcium absorption.
**Option C:** Vitamin E is present in eggs, acting as an antioxidant that protects cells from damage.

**Clinical Pearl / High-Yield Fact**
It's essential to note that vitamin C deficiency can lead to scurvy, a condition characterized by fatigue, malaise, and bleeding gums. A diet lacking in vitamin C can have significant health consequences.

**Correct Answer: D. Vitamin C.