Answer:
The pie graph represents 100 percent of the world's water supply.
Step-by-step explanation:
In this particular case, the purpose of the graph is to show all the sources of water supply in the world (which can be inferred from the title of the graph).
Each source contains proportionally large area of the pie graph (the circle) and is marked in different color. The more water the source provides, the greater area it contains.
Note that the sum of all sources (their percentages) adds up to 100%.
So, the inference for this graph can be that it shows from where 100% of our water comes from.