Explanation
Data views are system-generated tables that store information about subscriber actions, such as sends, opens, clicks, bounces, etc. Data views can be queried using SQL statements in automation studio or query studio to retrieve email metrics for analysis and reporting purposes. Data views store data for up to six months (or longer for some tables), and can be queried as frequently as needed, such as hourly or daily. References:
https://help.salesforce.com/articleView?id=sf.mc_as_data_views.htm&type=5

To recommend a scalable business unit hierarchy for Northern Trail Outfitters and its three subsidiaries, the consultant should suggest one parent BU and three child BUs with their own Sender Authentication Packages.
This will allow each subsidiary business to havetheir own branding, content, and subscribers, as well as access to aggregate reporting and shared subscribers from the parent BU. Each child BU should have its own Sender Authentication Package to authenticate its email sends with its own domain and branding. References:
https://help.salesforce.com/s/articleView?id=sf.mc_co_business_unit_setup.htm&type=5https://help.salesforce.c

Explanation
To send emails to loyalty members based on recent activity, a contact data entry source can be used to segment the data based on attributes and filters configured in Contact Builder. This allows for more flexibility and scalability than using a data extension entry source with an applied filter. References:
https://help.salesforce.com/s/articleView?id=sf.mc_jb_entry_sources.htm&type=5
https://help.salesforce.com/s/articleView?id=sf.mc_co_attribute_groups.htm&type=5

Journey Builder can be used to send a weekly coupon campaign with a reminder three days later at the subscribers' optimized send time. Journey Builder allows users to create cross-channel customer journeys that deliver personalized messages at the right time and on the right channel. Journey Builder can use Einstein Send Time Optimization to determine the optimal time to send an email based on each subscriber's past engagement behavior. References:
https://help.salesforce.com/s/articleView?id=sf.mc_jb_journey_builder.htm&type=5https://help.salesforce.com/s