What will happen to DC signal if positive probe connected to negative terminal and negative probe connected to positive of DC supply oscilloscope?

If the positive probe of the oscilloscope is connected to the negative terminal and the negative probe is connected to the positive terminal of a DC supply, the oscilloscope will display an inverted signal. This means that the voltage reading will be negative, effectively showing the opposite polarity of the actual DC voltage. The magnitude of the reading will remain the same, but the trace on the oscilloscope will appear flipped around the zero voltage line.