Question This sign is a: Answers Service sign. Regulatory sign. Warning sign. Stop sign. Explanation Warning signs are usually diamond-shaped and yellow with black lettering or symbols. They warn drivers about special situations or potential hazards ahead. This questions appears in the following tests: Louisiana Practice Test Florida Practice Test Texas Practice Test Missouri Practice Test New Jersey Practice Test North Carolina Practice Test Washington Practice Test Hawaii Practice Test Michigan Practice Test Vermont Practice Test Ohio Practice Test Indiana Practice Test New Hampshire Practice Test Minnesota Practice Test Alaska Practice Test Idaho Practice Test Colorado Practice Test North Dakota Practice Test Utah Practice Test Maine Practice Test Oregon Practice Test Massachusetts Practice Test Iowa Practice Test Wisconsin Practice Test Virginia Practice Test Montana Practice Test New Mexico Practice Test Oklahoma Practice Test Nevada Practice Test West Virginia Practice Test