Answer:
The answer is absolute threshold.
Step-by-step explanation:
The absolute threshold can be described as the minimal degree of a stimulus that can be detected. In this example, the stimulus is olfactory, but it may also be visual or auditory. The lower the threshold, the more sensitive the person is to a stimulus. Absolute thresholds tend to increase with age.
When measuring a person's absolute threshold, a stimulus should be detected at least 50% of the time.