The diagram illustrates a section of the carbon cycle. Which row correctly identifies processes W, X, Y and Z?
- AW combustion, X respiration, Y respiration, Z photosynthesis
- BW combustion, X photosynthesis, Y photosynthesis, Z respiration
- CW respiration, X combustion, Y respiration, Z photosynthesis
- DW respiration, X photosynthesis, Y combustion, Z photosynthesis