Which sentence contains an error in colon usage?

We need the following items at the market: lettuce, eggs, milk, and cheese.

Natalie has to wake up at 5:30 tomorrow morning.

Our teacher gave us a bit of advice: Start reviewing for the final exam now.

Brandon wanted to go fishing: but I wanted to go sailing.

1 answer

The sentence that contains an error in colon usage is:

Brandon wanted to go fishing: but I wanted to go sailing.

The correct way to express this idea would be to replace the colon with a comma or to rephrase it entirely. The colon should not be used before a conjunction like "but."