Egg is a poor source of
**Core Concept**
Eggs are a nutrient-dense food, but they lack certain essential nutrients, making them a poor source of specific vitamins and minerals. This is due to the egg's composition and the process of egg formation in the oviduct of birds.
**Why the Correct Answer is Right**
Eggs are a poor source of vitamin C, a water-soluble vitamin essential for collagen synthesis, iron absorption, and immune function. The egg's lack of vitamin C is due to the oviduct's inability to convert glucose into ascorbic acid, resulting in an egg that does not contain this critical nutrient. This is in contrast to animal tissues that synthesize vitamin C from glucose.
**Why Each Wrong Option is Incorrect**
**Option A:** Not applicable, as the correct answer is not specified.
**Option B:** Eggs are actually a good source of several B vitamins, including riboflavin, vitamin B12, and folate.
**Option C:** Eggs are a rich source of protein, containing about 6-7 grams per large egg.
**Clinical Pearl / High-Yield Fact**
Remember that eggs are not a significant source of vitamin C, which is essential for maintaining healthy connective tissue and preventing scurvy. Always consider vitamin C supplementation or intake from other sources, such as fruits and vegetables, to meet daily requirements.
**Correct Answer: D. Vitamin C.**