For defence exercise questions:
\begin{itemize}
\item Note the name of the exercise carefully,
\item Identify participating forces or countries,
\item Bilateral exercises usually involve two nations.
\end{itemize}
Step 1: HOPEX is a bilateral air exercise conducted by the Indian Air Force.
Step 2: The exercise is jointly held with the Egyptian Air Force.
Step 3: Therefore, HOPEX Exercise is related to Egypt.