C. The PLO continues to deny Israel's right to exist is your answer.
There has been numerous peace talks, however, the PLO continues to decline each one and continue the war (even though they stated that Israel started it, which is false). Israel fights a defensive war, and has offered to give agreements each time, in which they are not as favorable to Israel at all time, but Palestine does not accept anything short of elimination of the state of Israel. This puts PLO as being considered as a terrorist organization, and had been treated as such by Israel.
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