A scientist measured the mass of 9 samples of a substance. The data is shown in the table.
Sample 1 2 3 4 5 6 7 8 9
Mass (g) 2.7 4.3 3.1 3.2 2.8 2.9 3.1 2.8 3.1
Which data is an outlier?
A. 2.7g
B. 2.9 g
C. 3.1g
D. 4.3 g