To solve this problem, we need to match the essential elements with their functions in plants. Let's analyze each element:$\newline \bullet$a. Iron:$\newline$ - Iron is crucial for the biosynthesis of chlorophyll. It acts as a catalyst in the formation of chlorophyll molecules.$\newline$ - This matches with iii. Required for chlorophyll biosynthesis.$\newline \bullet$b. Zinc:$\newline$ - Zinc is involved in the biosynthesis of Indole Acetic Acid (IAA), a type of auxin, which is a plant hormone.$\newline$ - This matches with iv. IAA biosynthesis.$\newline \bullet$c. Boron:$\newline$ - Boron is essential for pollen germination and growth of pollen tubes.$\newline$ - This matches with ii. Pollen germination.$\newline \bullet$d. Manganese:$\newline$ - Manganese plays a role in the photolysis of water during photosynthesis, which is part of the light-dependent reactions.$\newline$ - This matches with i. Photolysis of water.$\newline$Now, let's match the items from the list:$\newline a \rightarrow iii, b \rightarrow iv, c \rightarrow ii, d \rightarrow i \newline$This corresponds to Option 2.