What is the most common source of errors during the Gram stain procedure?

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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.

The answer is c hope this

Im not sure if you still need this but the answer is 300 hz450 hz  i just did this lesson so , wish you the best of luck and take care