A、∀x F(x)→∃x F(x)
B、∀x F(x)→(∀x∃y G(x,y)→∀x F(x))
C、∀x F(x)→(∀x F(x)∨∃y G(y))
D、¬(F(x,y)→R(x,y))∧R(x,y)
A、∀x F(x)→∃x F(x)
B、∀x F(x)→(∀x∃y G(x,y)→∀x F(x))
C、∀x F(x)→(∀x F(x)∨∃y G(y))
D、¬(F(x,y)→R(x,y))∧R(x,y)