Before publishing her test of musical aptitude, professor reed first administered the test to a representative sample of people. this was most clearly necessary for test:

This can be necessary for test standardisation

Explanation: Test standardisation involves the process of evaluation by comparing different test results with a standard.

From the question it can be assumed that the individual that participated in the test did very well and in order for the process to publish the results, he had to compare results with other people to ensure that she the result is not a hoax.