Simply add a [p] tag at the end of any line that contains a [a], with the [p] followed by the point value for that answer. The value can be positive or negative.
[i] What are Jose and Viviane making?",
[o] [a] Bacon and Eggs [p] -10
[o] [a] Eggs and Toast [p] -5
[o] [a] French Toast [p] +5
If no [p] tag is added, then any [a] item or option is given a score of 1 when correct and any item or option left unmarked is given a score of 0 (the score doesn’t change).