___ you're late, I will be angry.

• A. When
• B. Unless
• C. If
• D. Because

Answer: (C)

This question tests the real conditional pattern used for future results. When you want to express a possible condition in the present that leads to a future consequence, you use if + present simple, then will + base verb. Here, the condition is being late, and the consequence is anger in the future. So the natural sentence is: If you’re late, I will be angry.

The other options don’t fit this meaning. Using When would imply a habitual or expected time rather than a conditional cause-and-effect in the future. Unless changes the sense to “I’ll be angry unless you’re late,” which is a different, less natural idea here. Because would give a reason, not a condition.