Write the next sentence in the following story.

How to clean copper roof
Wear non-slip shoes with a good tread.
When working on your rooftop, it's important to have the proper footwear so that you can stay steady and keep your balance. Otherwise, there's the potential to slip and injure yourself.

a. The manufacturer's instructions will say you have to wear a non-slip shoe to prevent yourself from sliding. With patent leather soles, there are no risks of sliding.; b. Socks and boots are the best options for preventing this. It's crucial that you wear safety gloves while you work so that you don't harm yourself.; c. In addition, the tread stones can create large glass chunks in your roof that are hard to clean. This is something you should avoid doing at all costs : Skip, or cook the dishes.; d. Sneakers or boots with a deep tread are typically best for working on rooftops. There are also boots that are made specifically for those who do roofing work.;. The answer should be
d.