Choose the incorrect sentence regarding the mechanism of absorption of elements.

• A
  In the first phase,an initial rapid uptake of ions into the 'free space' or 'outer space' of cells - the apoplast.
• B
  The passive movement of ions into the apoplast usually occurs through ion-channels.
• C
  The entry or exit of ions to and from the symplast requires the expenditure of metabolic energy,which is an active process.
• D
  The trans-membrane proteins function as selective pores.