The Registrar may, on the application in the prescribed manner of any person aggrieved and after giving the proprietor an opportunity of opposing the application, make such order as he thinks fit for expunging or varying any entry in the register to a certification trade mark, or for varying the regulations, on any of the following grounds, namely:--
         (a) that the proprietor is no longer competent, in the case of any of the goods or services in respect of which the mark is registered, to certify those goods or services;
         (b) that the proprietor has failed to observe any provisions of the regulations to be observed on his part;
         (c) that it is no longer to the public advantage that the mark should remain registered;
         (d) that it is requisite for the public advantage that if the mark remains registered, the regulations should be varied.