Life goes on by oliver tree
Answer:
a. unconditioned stimulus
Explanation:
Unconditioned stimulus: In psychology, the term "unconditioned stimulus" is described as one of the parts in the classical conditioning theory and is also denoted as UCS or US. It is defined as one of the stimuli that tend to trigger a particular response unreservedly what so ever is being presented without being trained in past and hence triggers the unconditioned response or UCR or UR.
In the question above, the given statement signifies the "unconditioned stimulus".
A RAIN GAUGE measures the amount of rain that has fallen over a specific time period. A WIND VANE is an instrument that determines the direction from which the wind is blowing.
