In One of the First Attempts to Discover the Speed

In one of the first attempts to discover the speed of light, Simon Newcomb in 1882 made 66 measurements of the time light takes to travel between the Washington Monument and his laboratory on the Potomac River. Why did Newcomb repeat his measurement 66 times and take the average of the 66 as his final result?

A) Averaging several measurements reduces any bias that is present in the instruments.
B) The average of several measurements is more reliable (less variable) than a single measurement.
C) Even if a measuring process is not valid, averaging several measurements made by this process will be valid.
D) Both A and B are correct.
E) Answers A, B, and C are correct.