Under PSDK there are two methods to display a choice. The classic method by event that should always be used when you have 2 to 4 options, and the script method when you need more than 4 choices.
Choices can use some specific codes.
The game switch
26 "Choix en haut" displays the choice in the top left corner of the screen.
Display a simple choice
To display a simple choice, use the message command to explain the choice and add the choice command right after to actually give a choice to the player.
This choice command allows cancelation. The cancelation is triggered when the player press the virtual key B. If you don't allow cancelation, the player won't be able to use the virtual key B and will be forced to choose an option.
Use a color for a choice option
Each choice option can have its own color. Use for this the
\c[$] code of the message command. (It affects the whole choice option!)
Use a Dynamic Text from RH or CSV
Dynamic texts in choices work the same as in Messages
Display more than 4 choices
To display more than 4 choices, use the script command :
choice and after that command, use the show message command. The result will be stored in the game variable you chose.