Dr. ingram deliberately varied the imageability of items on a list and later measured participants' recall of the items. dr. ingram conducted a(n) study.
a) correlational
b) naturalistic
c) experimental
d) observational

Dr. Ingram conducted an C. experimental study.

Explanation:

An experimental study is that in which the variables are in direct control of the researcher. He/she is in control of changing or adjusting them in order to reach an outcome.

Dr. Ingram varied the imageability of items on a list to measure the participants' recalling abilities. He is conducting an experimental study.

Let's see why the other options are not valid in this case:

disorders of the brain include both behavior disorders and other psychiatric illnesses. the primary difference between a behavior disorder and another type of psychiatric disorder is the presence of choice. psychiatric conditions are considered to be involuntary while in behavior disorders, choices are essential.

taking a bath requires the most water out of the given options because it takes a significant amount of water in order to fill a bathtub.