✅ Comprehensive and Detailed Explanation: The correct approach is one Parent Business Unit (corporate) with one Child Business Unit per franchise owner. This setup allows:

Corporate to control global assets, subscriber management, and brand compliance.

Franchise owners to localize messages within their own Business Unit, without accessing or changing corporate-controlled assets.

❌ Why Other Options Are Incorrect:

A: “Franchise owners” (plural) need individualized control; a single child BU won't be sufficient.

C: One Business Unit won't provide separation between different franchise operations.

D: Having a separate parent BU for each franchise is excessive, costly, and not scalable.

Exact Extract: Salesforce Help: Business Unit Overview

"Use Business Units to manage assets, permissions, and subscribers separately while maintaining corporate brand control across an enterprise."