Explanation:
Two testing types that an architect should recommend to ensure users don’t face platform slowdowns during peak business hours are: stress testing and performance testing. Stress testing is the process of testing the system under extreme load conditions, such as a large number of concurrent requests, to determine its breaking point and identify any potential bottlenecks or failures. Performance testing is the process of testing the system under normal or expected load conditions, such as the average number of requests per day, to measure its response time, throughput, and resource utilization. These testing types can help ensure that the web service can handle the expected volume and frequency of requests, and that it meets the performance and reliability requirements. Unit testing is not a testing type that an architect should recommend for this scenario, as it is the process of testing individual units of code, such as methods or classes, to verify their functionality and logic. Load testing is also not a testing type that an architect should recommend for this scenario, as it is the process of testing the system under a specific load condition, such as a fixed number of requests, to evaluate its behavior and performance. See Testing RESTful Web Services for more details.