The correct option is
D All of the above
The ground tissue of the plants is centrally placed. Parenchyma, sclerenchyma, and collenchyma commonly form the ground tissue. Parenchyma cells have thin primary walls and usually remain alive after they become mature. It forms the filler tissue in the soft parts of plants. Collenchyma cells have thin primary walls with some areas of secondary thickening. It provides extra structural support, particularly in regions of new growth.
Sclerenchyma cells have thick lignified secondary walls and often die when mature. Sclerenchyma provides the main structural support to a plant. So, option D is correct.