The following code:

Integer myInt = 5;

Correct because it is auto-boxing.

Incorrect because you cannot assign an int to Integer object.

Syntax error.

Correct because it is auto-unboxing.

The following statement:

Double dObj = new Double(3.4);

double x = dObj;

Correct because it is auto-unboxing.

Incorrect because a Double object cannot be assigned to a primitive data type.

Syntax error.

Correct because it is auto-boxing.