THE OR NO THE

The answer is C or A (depending on how you define Lebanon/the Lebanon)
Have the time of my life is a fixed expression.
We don't use THE with the names of the countries but THE LEBANON refers to the geographical region of the mountains of Lebanon that have "always" existed. LEBANON, without THE, is the "Republic of Lebanon", in other words, the state, or national entity that was recently created and became independent in 1943.
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