In order to use a Normal model to represent the distribution of a data set, which of the following statements must be true?
OA.
The distribution of the data set must be bimodal and clearly non-symmetric.
OB.
The distribution of the data set must be unimodal and clearly non-symmetric.
C.
The distribution of the data set must be bimodal and roughly symmetric.
D.
The distribution of the data set must be unimodal and roughly symmetric.