Which sign prohibits left turns?

• A. No Left Turn
• B. No Overtaking
• C. No Vehicles Carrying Explosives
• D. No Right Turn

Answer: (A)

A circular sign with a red border that shows a left-turning arrow with a diagonal bar across it communicates a prohibition on that maneuver. In the UK, prohibitory signs use a red-edged circle, and when the symbol inside shows a left turn with a slash, it means you may not turn left at that junction.

So, when you encounter this sign, you must not turn left; you can go straight or turn right only if those movements are allowed by other signs. The other options are different prohibitions (no overtaking, restrictions for vehicles carrying explosives, or no right turn) and do not apply to left turns. Some prohibitions may have extra plates indicating times or exceptions, so always check for those as well.