Question This road sign means: Answers All traffic must go straight. Turning on a red signal is prohibited. Left turns are prohibited. Explanation Regulatory signs provide notice to road users of traffic laws that must be obeyed. When posted at an intersection, this sign tells drivers that turning right or left on a solid red signal is prohibited. Pass your DMV Written Test with flying colors Take me to the cheat sheet Maryland This questions appears in the following tests: Maryland Practice Test 18 Maryland Practice Test 20