The best use of tone is in the line
OA) "Ah, make the most of what we yet may spend ..."
Explanation:
The line describes a feeling of longing and transience while also establishing that there is the impermanence of emotion that would dominate over the person,
This line from Omar Khayyam's Rubaiyat is symbolic of its poetic beauty and dexterity as a work of poetry.
It draws one's attention with this longingly romantic tone while also implying that it is sage like and important for people to know what it says.
The Rubaiyat contains such uses of tone a lot to draw the reader in for each fragment.