Write the next sentence in the following story.

How to recycle cigarette filters
Extinguish the cigarette by grinding out the flame.
For safety, extinguish cigarettes fully before attempting to recycle them. You can do this by throwing the cigarette on the ground, stepping on it, and twisting your foot.

Choose your answer from:
i. If you find it difficult to extinguish the cigarette on your ground, walk away from the site. Light cigarettes use one of two methods to perform this.;
ii. Do not use your shoe, with the paper and hair in the mess. Call a professional if your work and home are involved.;
iii. Sparks do not flip around easily after using this method. You can also use metal gloves instead if you have one, and proceed to destroy the cigarette with a lighter or match.;
iv. You should no longer see any glowing or smoke coming from the cigarette butt. If you have an ashtray, push the cigarette's lit end into it until the heat and smoke stop.;. The answer should be
iv.