What is the usual purpose of a blue circular traffic sign in Great Britain?
It announces that a temporary restriction has ended.
It gives a mandatory instruction or designates a route for stated vehicles.✓Correct answer
It warns of an unspecified hazard that may be ahead.
It marks a destination reached by leaving the current road.
Explanation
A blue circle generally tells road users what they must do or identifies a route reserved for a particular vehicle class. Treating it as a general warning would confuse it with the triangular warning-sign family.