Ideas that just might fit into the less than 10 ml of volume within a 17 cm piece of surgical silicone tubing. next we'll sift out the silly and see what might actually be a "viable" (workable and doable) idea.

a.) a destruction fo cells by viral reproduction

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.

i believe the answer is a or 1

c. heat from the poles back down towards the equator.