4. The Sheffer stroke ), also known as NAND", since plq is logically equivalent to -(p19), is universal, meaning that any proposition can be written using only the Sheffer stroke. All of the following except one are ways of writing -paqusing just the Sheffer stroke. Which proposition is *not* logically equivalent to p1q? O (91 (p|p))|(91 (p|p)) O (ql(pl (p1(p 1p))))|(9](pl(pl (p|p)))) O (91(pl (91 (p|p))))|(91(pl(ql(p|p)))) O ((pIq)| ((p 1p) | (q|q))) I ((pIq)| ((p 1p)| (q|q))) O ((p 1p)|((p1p) [(q|q)))/((p 1p) |((p 1p)| (9|q)))