Choose the incorrect sentence (for $C_4$ plants).

• A
  The particularly large cells around the vascular bundles of the $C_4$ pathway plants are called bundle sheath cells.
• B
  The light reaction takes place in mesophyll cells while $CO_2$ fixation occurs in bundle sheath cells.
• C
  In $C_4$ plants,bundle sheath cells have thick walls,impervious to gaseous exchange and lack intercellular spaces.
• D
  The chloroplasts in mesophyll cells exhibit grana organization.