\defineenumeration
  [question]
  [alternative=hanging,
   margin=2em,
   width=2em,
   text=,
   distance=none]

\starttext

\input ward

\startquestion
    \input zapf
    \startsubquestion
        \input zapf
    \stopsubquestion
    \input zapf
\stopquestion

\input ward

\stoptext
