A company’s cloud-based single page application consolidates data local to the application with data from on-premise and third-party systems. The diagram below typifies the application’s combined use of synchronous and asynchronous calls. The company wants to use the average response time of its application’s user interface as a basis for certain alerts. For this purpose, the following occurs: 1. Log every call start and finish date and time to a central analytics data store. 2. Compute response time uniformly as the difference between the start and finish date and time (A to H in the diagram). Which computation represents the end-to-end response time from the user’s perspective?