Below is an oscilloscope trace. What type of current produced it? Give the abbreviation, not the full name.

The oscilloscope trace you are referring to likely represents a waveform. Although I cannot see the trace itself, typical waveforms produced by various types of current include sinusoidal, square, or triangular patterns.

1. AC (Alternating Current) - Typically shows a sinusoidal waveform.
2. DC (Direct Current) - Generally presents as a straight line at a constant voltage.

If the trace shows a varying pattern, it is likely AC. If it's steady, then it represents DC.

To summarize: without viewing the trace, the most probable abbreviations for the current type are AC for alternating current or DC for direct current.