Which among the following is an incomplete poem by P.B. Shelley?

The correct option is “The triumph of life”.

The Triumph of Life was the last major work written by the English Romantic poet Percy Bysshe Shelley before his untimely death. Shelley began composing the poem in the summer of 1822 while living in Italy. The poem, written in the Italian terza rima stanza form, was left unfinished when Shelley tragically drowned on July 8, 1822, during a storm while sailing. As a result, the manuscript ends abruptly at line 548, mid-sentence, with the question: "Then, what is life? I cried."

To understand why the other choices are incorrect, let us examine them briefly:
• “Ode to the West Wind” is a completed, famous lyric poem written by Shelley in 1819 and published in 1820.
• “Queen Mab” is a completed, early philosophical poem in nine cantos, which Shelley privately printed and distributed in 1813.
• “The Daemon of the World” is also a completed poem. It is a revised and condensed version of the first two sections of Queen Mab, published in 1816.