The correct option is A Terminal leaflets
The tendrils of Pisum are modified terminal leaflets. The pea plant is a climber and climbs with the help of the modified terminal leaflets are called as tendrils produced at the apex of compound leaves and also form branched tendrils. Axial leaflets are the modified branches arising as buds in the axil of the leaf. A leaflet is a separate but distinct part of the leaf.
Thus, the correct answer is option A.