Signs communicate laws all drivers must understand and obey.

The answer is regulatory signs. The term regulatory sign defines a range of signs that are used to specify or emphasize traffic laws, rules or requirements which apply either at all times or at indicated times or places upon a street or highway, the neglect of which may constitute a violation, or signs in general that regulate public behavior in places open to the public. Traffic signs are the best example for this kind of signs. It is intended to instruct road users on what they must or should do (or not do) under a certain set of conditions. Other types may be signs positioned on streets and in parking lots having to do with parking, signs in public parks and on beaches or on or in architectural facilities prohibiting specific types of activities. 

overview:

this is a technology-dependent lesson that students can guide at their own pace of exploration and learning. students share what they learn through the use of twitter (or alternative classroom sharing medium like todaysmeet). the use of a social sharing platform like twitter gives students a place for sharing with a wider audience, for more effective means of communication with each other, for incorporating viewpoints from all students in the classroom, and a means to reference thinking and learning by the use of a hashtag at a later time. students will understand the role the allied air forces played in the normandy invasion. teachers can use this as a stand-alone lesson or offer more structure by guiding students through each source, one by one. teachers may learn more about the eighth air force by accessing the abmc’s strategic bombing campaign interactive.

answer; i believe the correct answer is (8) eight.