Ans: B. Schwabach's test(Ref Dhingra 7/e p23, 5/e p25-27)Lateralization of Weber's test to right implies either right-sided conductive deafness or left sided sensorineural deafness.Now in conductive deafness bone conduction is better than air conduction in Rinnie's test, hence the patient probably has sensorineural deafness involving the left ear, as per the findings of Rinnie's and Weber tests.In such a case, Schwabach's test should be performed to see the absolute bone.