Participating in a Psychology Study, You Find Yourself Sitting in a Room

Participating in a psychology study, you find yourself sitting in a room that is completely dark. The researcher adjusts the dial on a machine that displays a small spot of light. Across dozens of trials, the researcher finds the minimal amount of light needed for you to report seeing it 50% of the time. In this study the researcher measured your __________

A) difference threshold.
B) absolute threshold.
C) JND threshold.
D) Weber threshold.