Exam 2V0-72.22 topic 1 question 36 discussion

D is correct. https://docs.spring.io/spring-framework/reference/core/beans/environment.html#beans-using-propertysource

Option A is not correct: @PropertySource is not specifically used to designate the location of the application.properties file in a Spring Boot application. In a Spring Boot application, the application.properties file is automatically loaded from the classpath by default without needing to use @PropertySource. Option B is not entirely accurate: While you can use @PropertySource to load properties from an external property file, it allows you to load multiple key-value pairs rather than just a single property value. Option C is not correct: @PropertySource does not designate the file directory of the application.properties file in a Spring Boot application. Again, in Spring Boot, the application.properties file is automatically loaded from the classpath by default without needing to use @PropertySource.

why not D ? I can not see any problem with D

None are exactly correct. It is an annotation to be used in tests to specify properties files to be included. Also it overrides the standard application.properties file.