The correct option is B Plumule
Radicle is the first part of a seedling to emerge from the seed during the process of germination. The radicle is the embryonic root of the plant and grows downward in the soil.
Plumule is the young shoot of a plant embryo above the cotyledons, consisiting of the epicotyl and often of immature leaves.
Cotyledon is the significant part of the embryo within the seed of a plant. Upon germination, the cotyledon may become the embryonic first leaves of a seedling.
Ovule is the structure that gives rise to and contains female reproductive cells.
Thus, the correct answer is option (B), 'Plumule'.