In which of the following condition, positive Rinne test is seen

Rinne test: In this test air conduction of the ear is compared with its bone conduction. A vibrating tuning fork is placed on the patient's mastoid and when he stops hearing, it is brought by the meatus. If he still hears, AC is more than BC. Alternatively, the patient is asked to compare the loudness of sound heard through air and bone conduction.Rinne test is called positive when AC is longer or louder than BC. It is seen in normal persons or those having sensorineural deafness. A negative Rinne (BC > AC) is seen in conductive deafness. A negative Rinne indicates a minimum air-bone gap of 15-20 dB.Dhingra 6e pg: 22