Stability index, determined for evaluating the stability of oil–water viscous emulsions, based on electric conductivity changes during non‐destructive short heating–cooling–heating cycles, A. is defined as \(\frac{Δ}{h}\), where h is the change in the conductivity between 35°C and 45°C and Δ is the conductivity interval within the two heating curves at 35°C B. indicates the relative change in enthalpy between two cycles C. is defined as \(\frac{2Δ}{h}\), where h is the change in the conductivity between 35°C and 45°C and Δ is the conductivity interval within the two heating curves at 35°C D. indicates the relative change in conductivity between two cycles Choose the correct answer from the options given below: