Most likely Syrian. Jordan and Egypt wouldn’t. Lebanon only has a token air force and no fighters, just helos and some fixed-wing surveillance and transport planes. Iran is possible, but not likely; the easiest path would be traveling over Iraq and Jordan which WOULD have set off early warning systems—never mind how the US air defense controllers would have reacted if Iranian fighters were heading in the vicinity of the Green Zone. Plus, Turkey probably wouldn’t allow an Iranian overflight.
This leaves Syria as the most likely suspect.