Which detail from the poem sonnet 27 shows situational irony? А
The speaker realizes that he must be a slave to the image and thought of his
lover day and night.
B
The speaker thinks of making a mental pilgrimage to his lover since he cannot
close his eyes and rest.
С
The speaker, tired from having traveled all day, is unable to fall asleep because
his mind has decided to "wake up."
D
The speaker sees shadows in the night but is comforted when he visualizes his
lover, who appears like a jewel shining in the dark.

The detail from the poem sonnet 27 that shows situational irony is; С . The speaker, tired from having traveled all day, is unable to fall asleep because  his mind has decided to "wake up."

Situational irony occurs when the opposite of a supposed outcome transpires.  

The usage of situational irony can be seen in the text above because the expected outcome after the traveler's journey is a long sleep.

However, this is not the case as his mind decided to wake up.

So, this is the opposite of an expected outcome. Therefore, option C is correct.

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The detail from the poem Sonnet 27 that shows situational irony is:

С . The speaker, tired from having traveled all day, is unable to fall asleep because  his mind has decided to "wake up."

Explanation:

Situational irony takes place when one's actions (a character's or a speaker's, for instance) end up having the opposite result of what was expected.

Right at the beginning of the poem Sonnet 27, by Shakespeare, the speaker explains that he is exhausted after having worked and traveled all day. He says that he is in bed with the purpose of getting some rest. However - and this where the situational irony happens -, he is unable to fall asleep because his mind is wide awake, thinking of the woman he loves. Therefore, what takes place when he goes to bed is precisely the opposite of what he intended:

Weary with toil, I haste me to my bed,

The dear repose for limbs with travel tired;

But then begins a journey in my head

Source : Wikipedia

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