56.The carbon cycle involves a variety of processes that move and convert carbon between Earth systems. The diagram summarizes the main processes of the carbon cycle.

The carbon cycle is shown as a series of arrows that connect the atmosphere with plants and animals on the surface, as well as dissolved carbon dioxide in the water.

Ted is concerned about the rising carbon dioxide levels in the atmosphere, which scientists argue are causing global climate change. As Ted studies the diagram of the carbon cycle, he notices that photosynthesis is the only process that converts carbon dioxide from the atmosphere into the carbon compounds of the biosphere.

Which of the following questions that Ted might ask could be investigated by applying the methods of science?

A. How can scientists convince government leaders that climate change is a serious problem?
B. Should we invest in research to improve artificial methods of converting carbon dioxide to other compounds?
C. Is a change in global rates of photosynthesis affecting levels of carbon dioxide in the atmosphere?
D. What are the best strategies for fighting climate change or coping with its effects?