When I use new_multiple_choice, for example from https://webwork.maa.org/wiki/MultipleChoiceProblems, PDF hard copy generation with students answer results in error message
Package inputenc Error: Invalid UTF-8 byte "80. ... l.416 $\displaystyle \verb B$Without student answer there is no problem with PDF generation.
This is in v. 2.17, but as I remember I had the same problem with v. 2.16.