Multi-choice problem: Continue writing the next sentence in this paragraph:

How to make glow in the dark stepping stones
Clean the stones.
If you are applying paint, you need a clean surface to start with. Dust and dirt under the paint will cause problems with adhesion and you will end up with flaky paint.

Options are:
A). Once you have cleaned your stones, rinse them under water for up to one minute, and then dry them with a clean rag or coffee filter. Check your stone's hardness before placing it under the soap.
B). Wipe these clean off with cloth or paper towels. To make glow in the dark walking stones won't even enter the light, you'll need to clean them a lot.
C). Fill a syringe with a durable, water-based cleaner. Squirt lemon juice between the stones.
D). Wipe each stone down with soap and water. Then, wipe each stone down with a rag dipped either in water, acetone, or isopropyl alcohol.
D).