Answer:
In the diagram, X is pointing towards chloroplast, Z is pointing towards mitochondria, Y is pointing towards Cell wall and W is plasma membrane.
Step-by-step explanation:
Both chloroplast and cell wall are present only in plants but the one which helps in photosynthesis is chloroplast. So the answer is X. Chloroplast contains chlorophyll in the presence of which plant carry out photosynthesis.
6CO2 + 6H2O —> C6H12O6 + 6O2. This is the basic reaction which requires sunlight and chlorophyll.