An organic disorder whose symptoms tend to develop gradually and worsen over time is A bulimia
B. anorexia
C. delirium
D. dementia

Answer is in the photo. I couldn't attach it here, but uploaded it to a file hosting. link below! Good Luck!

cutt.ly/wzUiVyK

b

explanation:

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.