Marginal placentation refers to ovules present at one common margin, as in pea.

• A. Marginal Placentation
• B. Axile Placentation
• C. Placentation
• D. Perianth

Answer: (A)

Placentation describes how ovules are attached inside the ovary. Marginal placentation is when ovules lie along a single margin of a unilocular ovary, which fits the pea pattern where two fused carpels form a seam and ovules are arranged along that ventral margin. This creates a continuous row of ovules on one edge. Other patterns differ: axile placentation has ovules arranged around a central axis within a multi-locular ovary; parietal placentation attaches ovules to the walls of a multi-chambered ovary; basal placentation places ovules at the base; and free-central placentation features ovules on a central column rather than along a margin. Thus, marginal placentation best describes the pea arrangement.