Please choose the correct solution to the question: How can you keep swimming goggles cleaner longer?

Solution1: Wipe a smear of sulphuric acid on the inside of the goggles, then wipe it off, it will keep them cleaner longer.

Solution2: Wipe a smear of toothpaste on the inside of the goggles, then wipe it off, it will keep them cleaner longer.

Answer format: solution1/solution2
Answer: solution2