Answer:
I.
Explanation:
You can eliminate the other anwers to see which one has a toothed edge.
V: Has a smooth, rounded edge
IV: Has many smooth, rounded leaves that are oval-shaped.
I: Definitely has 'toothed' projections around the edge of the leaf, which is the characteristic of a Betula as described in the diagram above.
II: The edges of this leave are smooth, and the edges must be toothed, not the entire leaf. If the question asked for a toothed leaf, this would be the one, however, the edges are smooth instead of toothed.
