Choose the option that correctly identifies the figure of speech used…

The correct answer is Option (3) → Personification

Personification:

• The lines open John Donne's poem "The Sun Rising", in which the speaker scolds the sun for waking him and his beloved.
• Personification gives human qualities, feelings or actions to something that is not human.
• Deciding clue: the sun is addressed and scolded as "Busy old fool".
• Here the sun is spoken to as if it were a person: it is called a "busy old fool" and "unruly", it is questioned ("Why dost thou thus"), and it is said to "call on us" through windows and curtains like a meddling visitor.
  Example: The old house groaned in the storm.

Why the Other Options are Incorrect?

Option 1: Metaphor — Incorrect. A metaphor says that one thing is another, without "like" or "as". Calling the sun a "fool" is part of treating it as a person who can be scolded and questioned, which is personification.
Example: The classroom was a zoo before the teacher arrived.

Option 2: Enjambment — Incorrect. Enjambment is the running on of a sentence from one line of verse into the next without a pause. It is a feature of the arrangement of lines, not a figure of speech, and it does not describe how the sun is treated here.

Option 4: Synecdoche — Incorrect. Synecdoche uses a part to stand for the whole, or the whole for a part; the sun is named as itself, not through a part.
Example: The captain called all hands on deck.