The correct option is (c) Calorimetric biosensor
Easiest explanation: The diagram above represents the schematic diagram of a calorimetric biosensor. In this biosensor, the sample stream passes through the outer insulated box to the heat exchanger within an aluminium block. Later, it flows past the reference thermistor, into the packed bed bioreactor, containing the biocatalyst, where the reaction occurs. The change in temperature is determined by the thermistor and the solution is passed to waste. External electronics determines the difference in the resistance, and hence temperature, between the thermistors.