\label{numerical_wrong_answers} When switched into exam (``bubble sheet'') mode, LON-CAPA usually create wrong answers automatically. To specify wrong answers yourself, you need to provide an array of incorrect values to the throught the 'incorrect' attribute. You need to provide at least as many incorrects as 1 less than the number of bubbles on the exam. You can provide more if you want to. In Edit mode there is an 'Incorrect Answers:' field you can fill in. Minimal example problem: \begin{verbatim} Correct answer is 1.
\end{verbatim}