Which of the following best describes a normal distribution?

A normal distribution is best described as being bell-shaped and characterized by its mean and standard deviation. This shape implies that most of the data points cluster around the mean, creating a peak at the center, with the probabilities of values decreasing symmetrically as you move away from the mean in either direction. The standard deviation indicates the spread or width of the distribution; a smaller standard deviation results in a steeper curve, while a larger one produces a flatter curve.

This definition highlights key features of a normal distribution, including its symmetry and the fact that it encompasses a range of values in a predictable fashion determined by the parameters of the mean and standard deviation. This contrasts with other options, which describe distributions that do not exhibit these characteristics, such as being skewed or uniform, or having multiple peaks.