Which statement about Java wrapper types like Integer is true?

Which statement about Java wrapper types like Integer is true?

• A. They are mutable
• B. They are immutable
• C. They are not objects
• D. They are primitive types

Answer: (B)

Wrapper classes such as Integer are immutable. Once you create an Integer with a specific value, that value cannot be changed inside that object; if you need a different value, you work with a new Integer instance (or rely on autoboxing to obtain another one). This immutability is what makes wrapper types safe to share and use in collections, while still being distinct from primitive types, which are not objects. They are not primitive types, and they are indeed objects, so the statement that best describes them is that they are immutable.

Wrapper classes such as Integer are immutable. Once you create an Integer with a specific value, that value cannot be changed inside that object; if you need a different value, you work with a new Integer instance (or rely on autoboxing to obtain another one). This immutability is what makes wrapper types safe to share and use in collections, while still being distinct from primitive types, which are not objects. They are not primitive types, and they are indeed objects, so the statement that best describes them is that they are immutable.