Which of the following plant organs is always included in the root system of a plant?
a.
roots
b.
leaves
c.
stem
d.
all of these

Option A

Explanation:

The plant organs that is always included in the root system is roots.The root system in the plants consists of the structures that are below the ground.

Such structures are tubers, roots, rhizomes, et cetera. The main function of root system is to supply water, hormones, minerals to the plant and within the plant.

The roots also provide anchorage to the plants by binding tightly to the soil particles.

answer: tributaries flow into rivers.

wetland is a biome that develops when the water gets accumulated in a land exhibiting a huge depression. these form either seasonally or permanently. the water in the wetland comes from rivers, lakes, ocean, flood, rain or other sources. the wetlands includes mangroves, marshes and peatland.

tributaries flow into the rivers develops a wetland because such water will get deposited in the depression and will restrict the original flow of tributary water. hence, water with low drainage current combines with the river water.