Two column enumerate revtex

We have a list of small items

\begin{enumerate}
\item a
\item b
\item c
\item d
\end{enumerate}


which we would like to typeset as such

1. a             3. c
2. b             4. d


Normally we could use the multicol package. However if we are forced to use the revtex4-1 document class, we cannot use multicol as it is explicitly listed to be incompatible. How can we typeset this nonetheless?

If the enumeration should go from left to right, the tasks package is perhaps the right choice (but certainly not the only one, of course).

\documentclass{revtex4-1}