During a hearing test, many sounds were presented at such a low level of intensity that Mr. Antall could hardly detect them. These sounds were below Mr. Antall's:

The correct choice is based on the concept of the absolute threshold, which refers to the minimum level of stimulus intensity that an individual can detect. In this case, the sounds presented during the hearing test were at such a low intensity that Mr. Antall could hardly detect them, indicating that they were below his absolute threshold.

Understanding the absolute threshold is essential in sensory psychology because it defines the point at which a stimulus becomes noticeable to the senses. If the intensity of a sound is lower than this threshold, it would not be perceived by the individual, as it does not reach the necessary level for detection.

The other terms mentioned refer to different concepts related to sensory perception. The super threshold involves stimuli that are above the absolute threshold and detectable. The difference threshold pertains to the minimal difference in stimulus intensity needed to detect a change between two stimuli. The perceptual threshold, while related to the concept of perception, does not specifically define the point of minimum detection like the absolute threshold does.

Thus, the scenario where the sounds are barely detectable aligns perfectly with the definition of the absolute threshold.