A. @EntityScan and spring.jpa.* properties can be used to customize Spring Data JPA.

This is true because the @EntityScan annotation can be used to specify the base packages to scan for JPA entities, instead of using the default package of the main application class. The spring.jpa.* properties can be used to configure various aspects of Spring Data JPA, such as the database platform, the DDL generation, the show-sql flag, etc.

B. Any kind of Hibernate property can be passed to Spring Data JPA like spring.jpa.properties.xxx.

This is true because Spring Data JPA supports passing any Hibernate-specific property by using the prefix spring.jpa.properties. For example, we can use spring.jpa.properties.hibernate.format_sql=true to format the SQL statements generated by Hibernate.

REST stands for Representational State Transfer, which is an architectural style for designing web services that adhere to certain principles. One of these principles is statelessness, which means that each request from a client to a server must contain all the information necessary to understand the request, and that no session state is maintained on the server side. Another principle is uniform interface, which means that clients and servers communicate using a standardized protocol, such as HTTP, and use its features, such as headers and status codes, to exchange information about the resources and their representations.

A web slice test is a type of test in Spring Boot that focuses on testing only the web layer of an application, without starting a full server or requiring a real database. To isolate the web layer from other dependencies, such as services or repositories, mocks can be used to simulate their behavior and return predefined responses. To create and inject a mock for an existing bean in the application context, the @MockBean annotation can be used on a field or a parameter in the test class. This annotation will replace any existing bean of the same type with a mock created by Mockito.

Enable auto-configuration of the Spring Application Context, attempting to guess and configure beans that you are likely to need https://docs.spring.io/spring-boot/docs/current/api/org/springframework/boot/autoconfigure/EnableAutoConfiguration.html