Let the universe of discourse be the set of all cats. Consider the predicates: b(x) : x is black, I(@) : x has four legs What is an equivalent statement to the natural language sentence below? There exists a cat that has four legs but is not black Select one: O Vx(l(x) A -b(I) ) O Fx(1(x) A -b(x) ) O Ax(1(x) A -b(x) ) O Fr(l(x) Ab(x))