A: An outlier is a point that is an exception compared to the distribution of the data. In a histogram, it would appear as a bar away from the distribution with a lower height. We can't observe this in this distribution.
A do not apply.
B: A cluster is an accumulation of point in a certain interval. The interval given is 0 to 39. In the distribution, there are no points for this interval, so no cluster.
B do not apply.
Since A and B do not apply, C do apply.