Compound P and R upon ozonolysis produce Q and S, respectively. The molecular formula of Q and S is C8H8O. Q undergoes Cannizzaro reaction but not haloform reaction, whereas S undergoes haloform reaction but not Cannizzaro reaction. The option(s) with suitable combination of P and R, respectively, is (are):

Q undergoes Cannizzaro reaction, which means it has an aldehyde group without any α-hydrogen. It does not undergo haloform reaction, which means it does not have a methyl ketone group. Therefore, Q must be benzaldehyde (PhCHO). S undergoes haloform reaction, which implies it has a methyl ketone group (CH3CO-). It does not undergo Cannizzaro reaction, which means it cannot have an aldehyde group. Thus, S must be acetophenone (PhCOCH3). Since Q and S are formed by ozonolysis of P and R, we can deduce the structures of P and R.
Ozonolysis of an alkene cleaves the double bond, forming carbonyl compounds. Therefore, P must have a structure that, upon ozonolysis, forms two benzaldehyde molecules. This is possible if P is stilbene. Similarly, R must yield two acetophenone molecules upon ozonolysis. This means R is 1,2-diphenylethene. Therefore, the suitable combination of P and R is stilbene and 1,2-diphenylethene, respectively. This corresponds to option B.