The correct answer is option 'C' - fibrous roots.

Explanation:
Parallel venation refers to the arrangement of veins in the leaves of a plant. In plants with parallel venation, the veins run parallel to each other from the base to the tip of the leaf. This is in contrast to reticulate venation, where the veins form a network-like pattern on the leaf surface.

Plants with leaves having parallel venation are typically monocots, such as grasses, lilies, and orchids. These plants have fibrous roots.

Fibrous roots:
Fibrous roots are a type of adventitious root system. They are formed by the thin, thread-like roots that arise from the base of the stem or the lower nodes. In plants with fibrous roots, there is no main taproot, but rather a dense network of fine roots that spread out in all directions.

Characteristics of fibrous roots:
1. Network-like structure: Fibrous roots form a dense network of roots that spread out horizontally in the soil.
2. Absorption of water and nutrients: The numerous fine roots increase the surface area available for absorption of water and nutrients from the soil.
3. Anchorage: Fibrous roots provide stability and anchorage to the plant, preventing it from being easily uprooted.
4. Adaptation to shallow soils: Fibrous roots are well-suited for plants growing in shallow soils, as they can occupy a larger volume of soil and extract nutrients from a wider area.

Examples of plants with fibrous roots:
1. Grasses: Grasses, such as wheat, rice, and maize, have fibrous roots.
2. Lilies: Lily plants have fibrous roots that help anchor the plant in the soil.
3. Orchids: Orchids have fibrous roots that assist in absorbing moisture from the air and providing stability to the plant.

In conclusion, plants with leaves having parallel venation possess fibrous roots. This root system provides effective absorption of water and nutrients, as well as anchorage and stability to the plant.

C) Fibrous root