When whole blood is stored with an anticoagulant at $4^\circ C$, the ${K^ + }$ ions move out from the $RBC$ into the plasma. The most likely reasons for this is that

• A

  $RBC$ haemolyses and hence leakage of ${K^ + }$ ions

• B

  ${K^ + }$ ions become more mobile at $4°C$

• C

  Active transport ceases resulting in ionic equilibrium

• D

  The anticoagulant attracts the ${K^ + }$ ions into the plasma