The correct answer is B. Indicating instruments.
An indicating instrument is a type of electrical measuring instrument that indicates the instantaneous value of the electrical quantity being measured at the time at which it is being measured. It does not record the value, but simply indicates it on a scale.
An absolute instrument is a type of electrical measuring instrument that indicates the absolute value of the electrical quantity being measured, without the need for calibration.
A recording instrument is a type of electrical measuring instrument that records the value of the electrical quantity being measured over time.
An integrating instrument is a type of electrical measuring instrument that integrates the value of the electrical quantity being measured over time.