Refer to the Diagram Below Showing the 1941 Experiments of Samuel

Refer to the diagram below showing the 1941 experiments of Samuel Ruben and Martin Kamen that traced isotopes of oxygen through the process of photosynthesis. The Ruben and Kamen experiments demonstrated that

A) all the oxygen gas produced during photosynthesis comes from water.
B) CO₂ is the source of the oxygen released during photosynthesis.
C) the oxygen released by water is incorporated into sugars.
D) oxygen is needed to make rubisco.
E) NADPH is made during the Calvin cycle.