An operational definition of anxiety that has been helpful in measuring differences among people and changes as a result of situations is

A) facilitation (increase) of the startle reflex.
B) impairment (decrease) of the papillary reflex.
C) facilitation of the Babinski reflex.
D) impairment of the knee-jerk reflex.

Startle Reflex

An involuntary response to a sudden or unexpected stimulus, exemplified by the body jerking or flinching.

Operational Definition

A clear, precise definition of a variable in terms of how it is to be measured or manipulated in a specific study.

Anxiety

A psychological condition identified by intense unease, nervousness, or apprehension sufficient to disrupt normal daily life.