**Core Concept**
The normal curve, also known as the Gaussian distribution or bell curve, is a probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean. This distribution is a fundamental concept in statistics and is widely used in various fields, including medicine.

**Why the Correct Answer is Right**
The normal curve is characterized by its bell-shaped appearance, with the majority of the data points clustered around the mean. The mean, mode, and median of the normal curve coincide, and the mean is equal to the median, which is also equal to the mode. This is because the normal curve is symmetric about the mean. However, the statement that the value of the mean is 1 is incorrect, as the mean of a normal curve can be any real number, not just 1.

**Why Each Wrong Option is Incorrect**
**Option A:** The normal curve is indeed bell-shaped, with the majority of the data points clustered around the mean. This is a defining characteristic of the normal curve.
**Option B:** The normal curve is symmetric about the mean, which means that the mean, median, and mode are all equal. This is a fundamental property of the normal curve.
**Option C:** The mean, mode, and median of the normal curve coincide, which is a key characteristic of the normal curve.

**Clinical Pearl / High-Yield Fact**
A normal curve is symmetric about the mean, which means that the mean, median, and mode are all equal. This property is essential to understand in statistics and is widely used in various fields, including medicine.

**Correct Answer:**
✓ Correct Answer: D. Value of mean is 1