What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_12, if x_12 plays tennis, then x_12 is not sad. For all x_12, if x_12 writes a letter, then x_12 is sad. For all x_12, if x_12 drinks water, then x_12 is writing a letter. There is at least one x_12 for which x_12 will drink water.
There is at least one x_12 for which x_12 will write a letter. For all x_12, if x_12 drinks water, then x_12 is sad.