Final answer:
The sound that was heard in the statement is the distinct crunch of ruffled potato chips, which is an auditory detail describing the noise of eating potato chips.
Step-by-step explanation:
In the statement "The teacher heard the distinct crunch of ruffled potato chips", the sound that was heard is c) The distinct crunch of ruffled potato chips. This particular sensory detail is focused on the auditory experience and illustrates the sharp, distinctive sound that potato chips make when they are eaten. The other options, such as the teacher's voice, the sound of a door opening, and silence, are not relevant to the sensory detail described in the statement.