Which sequence of events gives rise to flaccid guard cells and stomatal closure at night ?
(A) low [Glucose] ⇒ low osmotic pressure ⇒ low pH ⇒ high pCO2
(B) low pH ⇒ high pCO2 ⇒ low [Glucose] ⇒ low osmotic pressure
(C) low osmotic pressure ⇒ high pCO2 ⇒ low pH ⇒ low [Glucose]
(D) high pCO2 ⇒ low pH ⇒ low [Glucose] ⇒ low osmotic pressure