The correct option is B Vascular bundles are closed
In the monocots, the vascular bundles are of the collateral and closed type. The closed vascular bundles lack the cambium and cannot show secondary growth. In the stem, vascular bundles are found scattered in the ground tissue. They are more in number at the periphery as compared to the centre. In the monocot roots, the vascular bundles are closed type an found in the stele.