Final answer:
Line C, with its visual scene of 'idle teenagers hanging around on corners' uses imagery to support the primary message of Viewpoint #2 by suggesting the negative outcomes of students quitting school.
Step-by-step explanation:
The author of Viewpoint #2 uses imagery in line C: "Then we’ll have even more idle teenagers hanging around on corners and getting into all kinds of trouble." This line conjures up a visual image that supports the primary message by suggesting a negative outcome for teenagers who become discouraged and choose to quit school. The use of the word 'idle' along with the scene of teenagers 'hanging around on corners' powerfully evokes a sense of wasted potential and the risks posed by a lack of educational engagement.