Step 1: Define the given word. 'Hazy' means indistinct, vague, or misty; not clear.
Step 2: Define the options. 'Plain' means simple or unadorned. 'Clear' means easy to perceive, understand, or see through; transparent. 'Light' relates to brightness. 'Dull' means lacking interest or brightness.
Step 3: Find the direct opposite. The direct opposite of something being hazy (unclear) is it being 'clear'.