To use an ArrayList in your program, you must import:1. the java. collections package

2. the java. awt package

3. Nothing; the class is automatically available, just like regular arrays.

4. the java. util package

5. the java. lang package

Option 4: the java. util package

Explanation:

ArrayList is one of the Java collections that offer some handy features to manipulate a list of elements. ArrayList is not available in a Java program by default without explicitly import it. To use ArrayList, we need to write an import statement as follows:

import java. util. ArrayList;

After that, we can only proceed to declare an ArrayList in our Java program. For example:

ArrayList studentNames = new ArrayList ();