Notification of Claim Determination – The plan administrator shall notify each participant in writing of his determination of benefits. If the plan administrator denies any benefit, such written denial shall include:

(c) Notice of Decision. If the Plan Administrator denies part or all of the claim, the Plan Administrator shall notify the claimant in writing of such denial. The Plan Administrator shall write the notification in a manner calculated to be understood by the claimant. The notification shall set forth:

(d) Notice of Decision. If the Plan Administrator affirms the denial of part or the entire claim, the Plan Administrator shall notify the claimant in writing of such denial. The Plan Administrator shall write the notification in a manner calculated to be understood by the claimant. The notification shall set forth the specific reason for the denial and a reference to the specific provisions of the Plan on which the denial is based.