A thermocouple is suddenly immersed in a medium of high temperature. The approximate time taken by the thermocouple to reach 98% of the steady-state value is

• A. Equal to the time constant of the thermocouple
• B. Equal to twice the value of the time constant of the thermocouple
• C. Equal to four times the value of the time constant of the thermocouple
• D. Independent of the time constant