Final Answer:
The command used to list the "magic" commands in Jupyter is A. %lsmagic.
Step-by-step explanation:
In Jupyter, the command used to list all "magic" commands is %lsmagic. Magic commands are special commands that provide additional functionality and control within the Jupyter notebook environment. %lsmagic displays a list of all available magic commands, including line magics (prefixed with %) and cell magics (prefixed with %%).
These commands can be used for various purposes, such as managing the notebook environment, accessing system information, and interacting with data. Options B, C, and D do not represent the correct syntax for listing magic commands in Jupyter.
Option A is the answer.