LINK is like a subroutine call: control passes to the linked program, and when that program returns, control comes back to the point right after the LINK in the calling program. XCTL, by contrast, transfers control to another program without keeping a return path — if the new program finishes without another transfer, control simply returns to CICS itself rather than to the original calling program. Since both statements describe genuinely distinct, correct behaviors of the two commands, the combined option is the right choice.