The ribbon.loadbalancer.strategy property in Ribbon can be configured to modify the load-balancing strategy used in a Spring Cloud application. This property allows you to specify the load-balancing algorithm, such as round robin, random, or weighted, that Ribbon should use when distributing requests among available service instances. Customizing this property is useful for tailoring the load-balancing behavior to meet the specific needs of your application.

Option 1 is correct. Monitoring logs and metrics can help identify if the spike in response times is caused by application code, database queries, or external service calls. Restarting the server or adding database replicas/network bandwidth may temporarily alleviate the issue but won't provide insights into the root cause. Addressing the root cause might involve optimizing code, database queries, or addressing external service bottlenecks, depending on the identified source.

In Spring Boot, the @ConditionalOnClass annotation is used to specify conditions based on the availability of a specific class in the classpath. It allows you to configure certain behavior only if a particular class is present, which can be useful for ensuring that your application behaves correctly in different environments or configurations.

The @WebMvcTest annotation is used for testing the web layer of a Spring Boot application. It loads only the web-related components, such as controllers, and mocks other components. In contrast, @SpringBootTest loads the entire application context, including all components.

The AccessDecisionManager is responsible for restricting access to application resources based on user roles in Spring Security. It evaluates user roles and permissions against the requested resource and decides whether access should be granted or denied. The other options play different roles in the Spring Security framework but are not primarily responsible for role-based access control.

In a Spring Boot project, additional metadata like project description and developer information is typically included in the README.md file in the project repository. This file serves as a documentation source and is commonly used to provide project details. While it's possible to include such information in other places like comments or build configuration files, the README.md is the most standard and prominent location.

In Spring Boot, you would use the @RestController annotation for creating components that handle HTTP requests and responses. Methods within this component should be annotated with @RequestMapping or its shortcut annotations like @GetMapping, @PostMapping, etc., to define the request mapping for each method. The @RestController annotation combines @Controller and @ResponseBody, making it suitable for RESTful web services.

To configure a custom cache manager in Spring Boot, you can define a bean of type CacheManager with the desired configuration in your application's configuration class. This bean will override the default cache manager, allowing you to customize caching behavior according to your needs. The other options are not standard ways to configure a custom cache manager. The @EnableCustomCaching and @CustomCacheManager annotations are not part of the standard Spring Boot framework, and directly setting the property is not a recommended approach.

In Spring Boot, the @ComponentScan annotation is used to indicate that a class should be considered as a candidate for creating beans. It allows Spring to scan packages and identify classes annotated with @Component, @Service, and other stereotype annotations, making them eligible for bean creation and dependency injection. It's a crucial part of Spring Boot's auto-configuration.

To optimize database connectivity in Spring Boot for high-concurrency scenarios, you should configure a connection pool and use asynchronous programming. A connection pool manages and reuses database connections efficiently, and asynchronous programming allows you to handle multiple concurrent requests without blocking threads, improving overall system responsiveness. The other options are either incorrect or not suitable for addressing high-concurrency scenarios.