The correct answer is (a) True
Explanation: True, To protect the probe from chemical attack, it must be encapsulated in a biologically inert material having a high electrical and chemical resistance, e.g. silicone rubber. The probes can generally be sterilized by chemical means. Probe calibration is carried out in 0.9% saline during manufacture and each probe is given a calibration factor that is engraved on the connector.