I hadn't finished talking to Halima, when she snapped my head off. This means that she

Analyze the question: The idiom is "snap someone's head off." The sentence says the speaker had not finished talking when Halima did this, so the question is about what the idiom means in that context.

Explain the concept: "To snap someone's head off" means to respond to someone suddenly in an angry, sharp, or rude way. It has nothing to do with physical violence. It is about harsh, irritable speech.

Go through the options:

• A. gave me a sharp slap – This takes the idiom literally. It is wrong, because the idiom is about speech, not a physical act.
• B. rudely interrupted me – This fits. The speaker had not finished talking, and Halima cut in angrily and rudely. It matches both the idiom's meaning of a sharp, angry retort and the context of being cut off mid-speech.
• C. hissed at me – Hissing is a sound of contempt or disapproval, not the meaning of the idiom.
• D. ordered me to stop talking – This is close, but the idiom does not mean giving a formal order. It means a sudden, angry reply.

Tip: When you see an idiom in WASSCE or JAMB English, reject the literal options first (such as the slap in option A). Then use the context clue in the sentence, here "hadn't finished talking," to choose among the figurative meanings.