The correct answer isA and C.To use a sophisticated pricing engine hosted as a service outside the org, the developer must make a call to the service and implement the sfdc_checkout.PriceCalculations interface12.The sfdc_checkout.PriceCalculations interface is a standard interface that defines the methods for calculating prices for a cart or an order1.The developer can use this interface to override the default pricing logic and integrate with an external pricing service12.The developer must also make a call to the external service using Apex REST or SOAP callouts3and handle the response data accordingly.
Use External Objects and Implement the sfdc_checkout.CartPriceCalculations are not the correct answers. External objects are a way to access data from external data sources in real time, but they are not suitable for integrating with a pricing service that requires dynamic calculations .The sfdc_checkout.CartPriceCalculations interface is a deprecated interface that was used for calculating prices for a cart only1.It has been replaced by the sfdc_checkout.PriceCalculations interface, which supports both carts and orders1.Reference:
B2B Commerce on Lightning Experience Developer Guide
B2B Commerce and D2C Commerce Developer Guide
Salesforce Accredited B2B Commerce Developer
sfdc_checkout.PriceCalculations Interface
Integrate with Lightning B2B Commerce
Apex REST Callouts
[Apex Web Services and Callouts]
[Work with External Data Sources]
[Access External Data With Salesforce Connect]