What is the cause of the varied colors in the canyon?
A. the way the river carved the rocks
B. the layers of dirt covering the rocks
C. the presence of different kinds of rocks
D. the combination of older and newer rocks

What is one unique way in which the medium of tv can affect a message? a. by allowing the audience to review information and reflect on it b. by limiting the amount of coverage any one topic gets c. by using images and sound to give information context d. by reporting some types of information but ignoring other types