To answer this question, let's go through the code step by step:

In the main method:

1. Set s = new HashSet(); - This creates a new HashSet object called s.
2. s.add(new Name("Donald", "Duck")); - This adds a new Name object with the first name "Donald" and last name "Duck" to the HashSet.
3. System.out.println(s.contains(new Name("Donald", "Duck"))); - This checks if a new Name object with the first name "Donald" and last name "Duck" is present in the HashSet using the contains method.

In the equals method:

1. if (!(o instanceof Name)) return false; - This checks if the passed object o is an instance of the Name class. If it is not, it returns false.
2. Name n = (Name)o; - This creates a new Name object n by casting the passed object o to the Name class.
3. return n.first.equals(first) && n.last.equals(last); - This checks if the first and last names of the passed Name object n are equal to the first and last names of the current Name object. If they are equal, it returns true, otherwise it returns false.

Based on the code, the output will be:

B. false

Explanation: The HashSet uses the equals method to check for object equality. In the equals method of the Name class, the comparison is based on the equality of the first and last names. Since the equals method is not overridden in the Name class, it uses the default implementation from the Object class, which checks for reference equality. Therefore, when calling s.contains(new Name("Donald", "Duck")), the HashSet will create a new Name object, and since it is a different object from the one added to the HashSet earlier, the contains method will return false.

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