Final answer:
Temporary signs in work zones typically have an orange background with black lettering, offering high visibility and signifying caution.
Step-by-step explanation:
The basic color for temporary signs in work zones used in construction and maintenance work areas have an orange background with black lettering. This color combination is highly visible and is universally recognized as a sign of construction or maintenance activity, where caution is advised. The color orange, being easy to see in various light conditions, is commonly used for safety purposes, not only on signs but also on the uniforms of emergency workers. On the other hand, black lettering provides a striking contrast against the orange background, making the message clear and legible from a distance.