Direct Sensory Perception Provides a Vital Background for the Information

Direct sensory perception provides a vital background for the information that comes from human and documentary sources since:

A) it provides secondhand information.
B) it is easy and the most economical way of collecting data.
C) it means firsthand seeing,feeling,hearing,smelling,and tasting.
D) it involves reading and reviewing documents.
E) top executives are involved in getting firsthand information.