Schering bridge is a very versatile AC bridge and is used for capacitor testing in terms of1. Capacitance value (magnitude)2. loss angle measurement3. simple balance detector like PMMC instrument4. providing safety to operators by incorporating Wagner earthing deviceWhich of the above are correct?

Schering bridge is a very versatile AC bridge and is used for capacito

1.	Schering bridge is a very versatile AC bridge and is used for capacitor testing in terms of1. Capacitance value (magnitude)2. loss angle measurement3. simple balance detector like PMMC instrument4. providing safety to operators by incorporating Wagner earthing deviceWhich of the above are correct?
A.	1 and 3 only
B.	3 and 4 only
C.	1, 2 and 4 only
D.	1, 2, 3 and 4
Answer» D. 1, 2, 3 and 4