Because the proration period isMonthly, the calculation denominator is the total number of days in the applicable monthly period. Because the boundary isAlign to Calendar, the relevant initial period is the calendar month of March. Finally, because partial periods are allowed, Salesforce calculates a proportional multiplier for the portion of March during which the subscription is actually active.

The correct conceptual formula is therefore:

Proration Multiplier = Days Used in March ÷ Total Days in March.

This is option B. The calculated multiplier is then applied to the standard monthly price of US$200 to determine the charge for the initial partial period.

Option A is imprecise because the calculation is based on days of service actually used within the partial period, rather than a generic concept of “remaining days.” Depending on date-inclusion rules, these expressions can otherwise be interpreted differently. Option C is clearly inconsistent with the configuration because the defined proration period is monthly, not annual.

The critical exam principle is that proration follows the configuredproration period, period boundary, and partial-period policy.

Study Guide Reference:Configure, Price, Quote — Proration; subscription pricing; calendar-aligned partial periods.

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