Photosynthesis is the process by which plants use the energy from sunlight to produce sugar The conversion of unusable sunlight energy into usable chemical energy, is associated with the actions of the green pigment chlorophyll. Most of the time, the photosynthetic process uses water and releases the oxygen.

The chemical reaction associated with photosynthesis is

6H2O + 6CO2 --------> C6H12O6 + 6O2

Water Carbon Dioxide Starch Oxygen

Now coming to your question

Now our hypothesis says
Quote:Hypothesis: Oxygen is a product of photosynthesis.

Now read the given options A B C D and E carefully

Quote:A. Water is a reactant as well as a product in photosynthesis.

The given hypothesis says that oxygen is product of photosynthesis and doesn't says anything about water so this statement is wrong

Quote:B. At least some of the oxygen atoms in carbon dioxide appear in the starch formed by hypothesis.

Similarly no reference about startch or carbondioxide in hypothesis ,so this statement too can't be concluded from given hypothesis

Quote:C. Oxygen is released at a greater rate when plants are illuminated with red light tha when they receive green light.

No reference about this statement too.

Quote:D. The leaf surface contains pores through which carbon dioxide and oxygen can move.

This statement can be infereed from the hypothesis as oxygen might be coming out of those pores

Quote:E. The oxygen atoms in water do not appear in the starch formed by photosynthesis

No reference about this statement too.

So only option D is correct