The correct answer is letter A
The 1948-9 “independence” war (called by the Palestinians - “disaster”) culminated with the signing of Israel's armistice agreements with Egypt, Syria, Lebanon and Transjordan and the demarcation of lines armistice provisionals, the green lines, which were not considered as definitive borders (except the border with Lebanon) precisely because the Palestinian question has not yet been resolved. It is these lines, then, that are mentioned when talking about reverting to pre-1967 limits.
This question of borders was then definitively resolved in 1967, with the advent of the Six Day War, which was one of the most important events in the history of Israel. In that war, Israel not only tripled its territory, incorporating the Golan Heights, the West Bank, the Gaza Strip and the Sinai Peninsula - with definite borders - but also demonstrated to the enemies of the region its enormous military and strategic potential, gaining a much greater weight in the regional balance of power.