Select from options: Continue writing the next sentence.

How to use teeth whitening strips
Read the instructions carefully.
Although most whitening strips are applied and used in a similar manner, some brands may have different instructions. Always read the instructions fully and be aware of any side effects before using any whitening strip or whitening product.

Choose from:
a). Some brands of whitening strips may ask you to only use the strip for 2-3 days. Use a baking soda whitening strip to fill in stains..
b). Talk to your dentist if you are unsure what you should do with your teeth after using it. Some whitening strips may cause different side effects than others..
c). Some versions of whitening strips are available over-the-counter and others are available over-the-counter. Be sure to read the manufacturer's instructions carefully and always follow these directions..
d). Misuse can cause damage to your teeth, gums, and health. Instructions can vary between brands, always fully read the instructions before use..
Answer:
d).