How might upward growth of cities be a better choice than outward growth?
a.
upward growth affects less land area than outward growth.
b.
upward growth moderate pollution problems.
c.
upward growth has no limitations.
d.
upward growth has no environmental impact.

Option A, Upward growth affects less land area than outward growth

Explanation:

Upward growth of cities is nothing but the construction of tall building (or vertical development). This causes development of compact cities in which several component of cities are included into a small space due to which land requirement reduces. In other case , cities growing in outward direction (horizontal growth) require large piece of land to accommodate all its components. Thus, upward growth is a better choice as compared to the outward growth in lieu to requirement of lesser land area.

Hence, option A is the correct answer

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.