Research on Mental Imagery Suggests That There Is/are

Research on mental imagery suggests that there is/are:

A) just one type of mental imagery tied to the visual modality.
B) two types of mental imagery,one that preserves visual detail and one not tied to the visual modality.
C) one type of mental imagery that encodes spatial information and is not tied to the visual modality.
D) two types of mental imagery,one tied to the visual modality and one to the verbal.