What type of definition is the following? “CDD lymphocyte counts are t

What type of definition is the following? “CDD lymphocyte counts are the measure of immune function.”

a. Conceptual
b. Operational
c. Physiological
d. Theoretical

ESSAYBID ANSWER

ANS: B
An operational definition is derived from a set of procedures or progressive acts that a researcher performs to receive sensory impressions that indicate the existence or degree of existence of a variable. An operational definition is developed so that a variable can be measured or manipulated in a concrete situation.
A conceptual definition is the theoretical meaning of a variable.
These are physiological measurements, but the terms within the stem of the question are not defined physiologically. A physiological definition would provide an accurate description of the concept on a biologic level.
The conceptual definition can sometimes be a theoretical definition.