Answer:
The absolute threshold
Explanation:
In neuroscience and psychology, the absolute threshold refers to the lowest amount/intensity of an stimulus that a person can detect approximately 50% of the time. In other words, it is the lowest intensity of a visual, hearing, touch stimulus, that a person is able to detect.
In this example, you go to a hearing test and you are supposed to raise your hand whenever you hear a tone. Once the test is finished, the audiologist tells you that the test is designed so that some tones are so quiet you cannot hear them half of the time. In other words, since you can only detect them approximately 50% of the time, these tones would be in the absolute threshold since they are so low you can only detect them 50% percent of the time