Let's break down the Venn diagram and answer the questions.

Venn Diagram Analysis:

• Cats Only (13): These people prefer only cats.
• Dogs Only (8): These people prefer only dogs.
• Birds Only (9): These people prefer only birds.
• Cats and Dogs Only (4): These people prefer both cats and dogs, but not birds.
• Cats and Birds Only (7): These people prefer both cats and birds, but not dogs.
• Dogs and Birds Only (8): These people prefer both dogs and birds, but not cats.
• All Three (1): These people prefer cats, dogs, and birds.
• No Preference (6): These people have no preference for any of the animals.

Questions:

**a. How many people preferred cats, but not dogs?