Concept:The antonym of a word is its opposite in meaning. 'Deliberate' means done with careful thought and planning.
Explanation:'Deliberate' refers to an action that is intentional and well-considered.
'Rash' means acting without thinking, ignoring possible consequences.
Thus, 'rash' is the direct opposite of 'deliberate'.
Option A ('Calculated') means carefully planned, a synonym.
Option C ('Intentional') means done on purpose, also a synonym.
Option D ('Cautious') means careful to avoid danger, not opposite.
Only 'rash' contrasts with the idea of careful deliberation.
Answer:Rash (Option B)