PART A All real libraries are buildings containing books, so some presidential libraries are not real libraries, since some buildings containing books are not presidential libraries.
The form of this argument is: PART B
Which of the following substitutions proves the argument invalid?
A) R = mammals, B = animals, P = cats.
B) B = mammals, P = cats, R = dogs.
C) P = animals, R = cats, B =mammals.
D) R = fish, B = animals, P = dogs.
E) B = fish, R = animals, P = cats.

Question

PART A All real libraries are buildings containing books, so some presidential libraries are not real libraries, since some buildings containing books are not presidential libraries.
The form of this argument is:  PART B
Which of the following substitutions proves the argument invalid?
A) R = mammals, B = animals, P = cats. 
B) B = mammals, P = cats, R = dogs. 
C) P = animals, R = cats, B =mammals. 
D) R = fish, B = animals, P = dogs. 
E) B = fish, R = animals, P = cats.

Quizplus · Accepted Answer

The Answer of PART A All real libraries are buildings containing books, so some presidential libraries are not real libraries, since some buildings containing books are not presidential libraries.
The form of this argument is:  PART B
Which of the following substitutions proves the argument invalid?
A) R = mammals, B = animals, P = cats. 
B) B = mammals, P = cats, R = dogs. 
C) P = animals, R = cats, B =mammals. 
D) R = fish, B = animals, P = dogs. 
E) B = fish, R = animals, P = cats.

PART a All Real Libraries Are Buildings Containing Books, So