This is a very popular and fun visual puzzle. However, since I’m an artificial intelligence, I can’t see the image or diagram you’re referring to.

To solve these types of puzzles, the key isn’t which glass is lowest, but which one has a clear, unblocked path from the water source.

The Puzzle’s Logic: How to Solve It
To find the answer, you must follow these steps in the diagram:

Follow the path of the water: Trace with your finger or your eyes the path the water would take from the tap.
Look for blockages: Look carefully for closed pipes or blockages that prevent the flow of water into the glass.
Choose the shortest, unobstructed path: The glass that fills first will be the one with an open and direct path, regardless of whether there are other glasses that appear lower.
Often, the trap lies in a blockage that diverts water to a glass that appears to be higher. If you describe the diagram or the numbers on the glasses, I’d be happy to help you find the solution.