Options :

1. Large colorless empty cells in the epidermis of grass leaves - Subsidiary cells

2. In dicot leaves, vascular bundles are surrounded by large thick-walled cells - Conjunctive tissue

3. Cells of medullary rays that form part of cambial ring - Interfascicular cambium

4. Loose parenchyma cells rupturing the epidermis and forming a lens-shaped opening in bark - Spongy parenchyma