The process being described in the diagram is Glycolysis; Thus the answer is 2ATP.
The initial glucose 6-carbon molecule that is eventually broken down into 2 pyruvate 3-carbon molecules. Notice that 2 ATP are initially invested for a total of 4 ATP to be released. The Net ATP Production is 4ATP (released)-2ATP(invested) = 2 ATP.
Check the attached image for more explanation;
