The distribution would exhibit a negative skew.

A type of distribution in which more values are concentrated on the right side(tail) of the distribution graph while the left tail of the distribution graph is longer is called negatively skewed distribution.  Or a distribution is said to be negatively skewed or skewed to the left if the scores of the distribution falls mainly to the right of the graph and less to the left i.e. the lower scores are very few as compared to the high scores.

Here we are given that the three students who scored below 140 were dropped that means the some of the low scores are now dropped from the graph. Therefore, if 3 of the students who scored below 140 decide to drop the class, the shape of the distribution will be negative skewed or the distribution would exhibit a negative skew.

Find out more information about negative skewed distribution here: