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

How to grout wall tile
Put on safety protection.
Use rubber gloves, eye protection, and a smock. If you don't put on safety protection, you could potentially hurt yourself.

Pick from: A). Step into a small container, coat in petroleum based, brown goo, or other commercial-grade product; and tap the container against a nearby surface to knock out grout. Test grout on a level surface.; B). If your grout doesn't stop there, the tile may accidentally break down. Use the wall grout drops to prevent losing adhesion in the shower with the tile.; C). This is especially true for eye protection, as you may get grout in your eyes without it. Make sure the room you're working in is properly ventilated.; D). This is because grout can cause serious damage to the walls, and you should keep that in mind as you begin to grout tile tiles. Remember that you can grout concrete slabs without any knives, forks, and roller blades.;
C).