Which plant is a classic example of a papilionaceous flower?

• A. Sunflower
• B. Rose
• C. Mango
• D. Pea

Answer: (D)

Papilionaceous flowers are the butterfly-like blooms of many legumes, with a distinctive three-part corolla: a large upper banner petal, two lateral wings, and two lower keel petals that are often fused to form a boat-shaped structure that encloses the reproductive organs. This specialized arrangement is a hallmark of the bean family.

The pea is the classic example because its blossom clearly shows the banner, wings, and keel, making the butterfly-like shape immediately recognizable. The other options don’t exhibit this combination: sunflowers are composite heads rather than a single papilionaceous flower; roses have radial, five-petaled blooms; mango flowers are simple and lack the characteristic legume corolla structure.