What is the source of measurand?a.Human body surfaceb.Trasducer of biosensorc.Sensors of biosensord.All of these

The source of measurand can be all of these - human body surface, transducer of biosensor, and sensors of biosensor.

1. Human body surface: In some medical or health-related applications, the human body surface can be the source of measurand. For example, in measuring body temperature, the heat radiated from the body surface is the measurand.

2. Transducer of biosensor: A transducer is a device that converts one form of energy to another. In a biosensor, the transducer can convert a biological response into an electrical signal. So, the output of the transducer can be the measurand.

3. Sensors of biosensor: The sensors in a biosensor can detect specific biological, chemical, or physical processes and produce a measurable response. So, the output of the sensor can also be the measurand.

Therefore, depending on the specific application and context, the source of measurand can be any or all of these.