Given that B(a) means “a is a bear” F(a) means “a is a fish” and E(a, b) means…

2020

B(a) means “a is a bear”
F(a) means “a is a fish” and
E(a, b) means “a eats b” 

∀x[F(x) ⇒ ∀y(E(y, x) ⇒ B(y))] 

Answer: D. Only bears eat fish — The formula ∀x[F(x) ⇒ ∀y(E(y, x) ⇒ B(y))] translates to: For any entity x, if x is a fish, then for any entity y, if y eats x, y must be a bear. This means…

1. A.

   Every fish is eaten by some bear

2. B.

   Bears eat only fish

3. C.

   Every bear eats fish

4. D.

   Only bears eat fish

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