Question

traffic signals are often controlled by devices that detect traffic and are placed under the pavement. in the middle of the intersection. over the roadway. both a and c

Explanation:

Traffic - detecting devices for traffic signals are often placed under the pavement (e.g., inductive loop detectors) and over the roadway (e.g., video - based detectors). The middle of the intersection is not a typical placement for these detection devices.

Answer:

D. both A and C