Which of the following is an example of integrating type measuring instrument?

Option 4 : Ampere-hour meter

Based on the nature of the operation, instruments can be classified into three types.

1. Indicating Instruments: These indicate the quantity being measured by means of a pointer that moves on a scale. These instruments indicate the instantaneous value of the electrical quantity being measured at the time at which it is being measured.Example: Ammeter, Voltmeter
    
2. Recording Instruments: These instruments record continuously the variation of any electrical quantity with respect to time. In principle, these are indicating instruments but so arranged that a permanent continuous record of the indication is made on a chart or dial.Any electrical quantity like current, voltage can be recorded by a suitable recording mechanism.Example: A potentiometric type of recorder used for monitoring temperature records the instantaneous temperatures on a strip chart recorder.
    
3. Integrating Instruments: These instruments record the consumption of the total quantity of electricity, energy etc. during a particular period of time. These instruments give reading for a specific period of time but no indication of reading for a particular instant of time.Example: Ampere-hour meter, Energy meter, kilovolt ampere-hour meter.