Final answer:
The mode is defined as the most frequent value in a data set and can be a measure of central tendency that is helpful in identifying the most common outcome.
Step-by-step explanation:
The mode is defined as D. The most frequent value in a data set. The mode is a measure of central tendency that identifies the value that appears most often in a data set. It's possible to have more than one mode in a data set if multiple values occur with the same highest frequency; such a data set is called bimodal. Unlike the mean or median, the mode can be used for both numerical and categorical data and is particularly helpful in identifying the most common outcome or preference in the data.
Measures of the center of the data also include the mean, also known as the arithmetic average, and the median. The mean sums up all the values and divides by the count, representing an overall average, while the median is the middle value when the data are ordered, more resistant to outliers.