Timothy is a construction worker in one of the leading firms of a city. His employment contract includes a clause which says he cannot work as a construction worker within the city for fifteen years once he leaves the company. This clause is:

A) Only illegal if it violates state or federal antitrust laws.

B) Illegal as a contract in restraint of trade.

C) Legal because the employer can add any constraint to the agreement.

D) Illegal as it is injurious to public service.