Succession in a $6 \ m$ deep pond exhibits a sequence of

• A
  Submerged Plants $\rightarrow$ Reeds $\rightarrow$ Herbs $\rightarrow$ Floating Plants $\rightarrow$ Shrubs $\rightarrow$ Trees
• B
  Floating Plants $\rightarrow$ Submerged Plants $\rightarrow$ Reeds $\rightarrow$ Herbs $\rightarrow$ Shrubs $\rightarrow$ Trees
• C
  Shrubs $\rightarrow$ Trees $\rightarrow$ Submerged Plants $\rightarrow$ Floating Plants $\rightarrow$ Reeds $\rightarrow$ Herbs
• D
  Submerged Plants $\rightarrow$ Floating Plants $\rightarrow$ Reeds $\rightarrow$ Herbs $\rightarrow$ Shrubs $\rightarrow$ Trees