The correct option is A party to the arbitration agreement
It has been under the section 2 (1) (h), that a party means a party to the arbitration agreement. Arbitration is a legal technique for the resolution of disputes outside the courts, wherein the parties to a dispute refer it to one or more persons (the "arbitrators", or "arbitral tribunal"), by whose decision the "award" they agree to be bound. An arbitrator serves as the decision-maker and referee in an arbitration proceeding, much like a judge during a court case.