Which of the following poems is not written by Sylvia Plath?

The correct option is "To Ariel".

Sylvia Plath (1932–1963) was a preeminent American poet who pioneered the genre of confessional poetry. To determine which poem was not authored by her, we can examine each option:
• Lady Lazarus: Written in 1962, this is one of Plath's most celebrated poems. It is heavily associated with themes of suicide, resurrection, and performance, and was published posthumously in her 1965 collection, Ariel.
• Ariel: This is the title poem of her famous 1965 collection. Written in October 1962, the poem uses the literal and metaphorical imagery of a horse ride at dawn to explore themes of transformation, ecstasy, and the loss of control.
• Daddy: This is another of Plath's most famous and intense poems, also written in late 1962. It features controversial metaphors comparing her father to a Nazi and herself to a Jew, expressing the complex process of reclaiming her autonomy after his death.
• To Ariel: There is no poem titled "To Ariel" in Sylvia Plath's bibliography. While "Ariel" is a central piece of her work, "To Ariel" is a distractor and was not written by her.

Therefore, "To Ariel" is the correct answer as it is the only poem listed that Sylvia Plath did not write.