A selenium-activated protein P catalyses a metabolic reaction that results in release of two $\mathrm{H}^{+}$ions. Expression of P is induced by lactose. In an experiment, cells were grown for 1 hour in selenium and lactose containing media resulting in a net concentration of $10^6 \mathrm{M} \mathrm{H}^{+}$per cell. Selenium and lactose were removed from the media and cells were grown for another 10 generations. Assuming that all other proteins are expressed at a constant level, the net change in pH inside the cell at the end will be _____

• A

  $1$
• Correct answer
  B

  $3$
• C

  $11$
• D

  $6$

Hence, the correct answer is option: 'B'.