Concept:A dicot leaf has identifiable external parts such as the apex, midrib, lamina, and axil.
Explanation:Part I is the tip of the leaf, called the apex.
Part II is the central prominent vein, called the midrib.
Part III is the broad green expanded portion, called the lamina.
Part IV is the angle between the leaf and the stem, called the axil.
These identifications match option D.
Answer:D. apex, midrib, lamina, axil
