The correct option is D Bean
The flowers of family papilionaceae have butterfly shaped corolla (papilionaceous corolla). Posterior or outermost petal is the largest and is called standard or vexillum, two lateral petals are similar and generally clawed called wings or allae and the two anterior petals called keel are fused enclosing stamens and carpels. This type of petal arrangement in found in bean, gram, pea etc.