Critical thinking requires that a. conclusions be held constant after their initial determination b. conclusions be adjusted as necessary to incorporate new knowledge c. information from a particular source only be verified the first time the source is used d. there be a single solution to a particular problem

B. conclusions be adjusted as necessary to incorporate new knowledge

Critical thinking refers to the process of creating well thought, logical and sound judgments. It requires not only receiving and accepting arguments but verifying and testing the validity and truth in all the arguments presented. 

Wetlands form where water and land meet. a lake with a wetland fringe can fill in with decayed plant and animal material to become a wet meadow. a pond can fill in to become a bog or fen. sediment can fill in a river marsh to become a swamp.flooding of coastal lowlands from rising sea levels has created broad coastal marshes that are protected from wave action by barrier islands or reefs. coastal wetlands also form when rivers deposit sediment as they reach the ocean. plants then take root and hold the soil firm against the forces of tides and waves.