To answer this question, let's go through each option to understand why it is correct or incorrect:
Option A) Packages can be nested - This option is incorrect because packages cannot be nested in Java. However, classes can be nested within a package.
Option B) You can pass parameters to packages - This option is incorrect because packages do not have a direct mechanism for accepting parameters. However, you can pass parameters to classes or methods within a package.
Option C) A package is loaded into memory each time it is invoked - This option is incorrect. Packages are not directly invoked or loaded into memory. Instead, classes within a package are loaded into memory when they are used.
Option D) The contents of packages can be shared by many applications - This option is correct. Packages in Java provide a way to organize and group related classes together. The classes within a package can be accessed and used by multiple applications or modules.
Option E) You can achieve information hiding by making package constructs private - This option is correct. In Java, you can use access modifiers such as "private" to control the visibility of package constructs (classes, methods, variables). By making package constructs private, you can restrict their access to only within the package, achieving information hiding.
Therefore, the correct answer is D, E. These options are correct because packages allow for sharing contents among multiple applications and achieve information hiding by making package constructs private.