To meet the requirement of a qualifying period resetting on a specific date (March 31st) for all members, the Fixed tier model must be used. This model establishes a uniform tier assessment period for the entire program, unlike the Anniversary model which is based on individual member enrollment dates.

The second requirement explicitly states that the member's tier is not extended upon expiration. The No Extension setting for the 'Extend Tier Expiration' field directly implements this rule, ensuring that a member's tier status is re-evaluated and potentially downgraded at the end of the fixed period without any grace period.

A. Extend Expiration = member enrollment anniversary: This setting explicitly extends a member's tier, which directly contradicts the requirement that the tier is not extended.

C. Tier-model = anniversary: This model bases the qualifying period on each member's unique enrollment date, which conflicts with the requirement for a single, universal reset date for all members.

1. Salesforce Help Documentation, "Set Up Loyalty Tier Groups":

Tier Model: "Select the model that determines the qualifying period for members of the tier group. Fixed: The qualifying period is the same for all members of the tier group. Anniversary: The qualifying period is based on the enrollment date of each member." This supports the choice of 'Fixed' (B) over 'Anniversary' (C).

Extend Tier Expiration: "Select whether to extend the expiration of members' tiers. If you select to extend the expiration, specify the period for which the tier is extended. No Extension: The member's tier isn't extended." This supports the choice of 'No Extension' (D) over any extension option (A).

2. Salesforce Loyalty Management Developer Guide, "LoyaltyTierGroup" Object Reference:

TierModel Field: The documentation for this field describes the 'Fixed' and 'Anniversary' picklist values, confirming that 'Fixed' is used for a common qualifying period for all members in the tier group.

ExtendExpiration Field: The documentation for this field describes the 'NoExtension' picklist value, which specifies that the member's tier is not extended upon expiration.