Write the next sentence in the following story.

How to check cats for worms
Look for changes to the cat's coat.
A cat's fur is usually lustrous, but if your cat has worms, its coat might become dull or flat looking.
This can occur because of dehydration or poor absorption of nutrients resulting from the parasite infection.

OPTIONS:
a). Check your cat's gums. A healthy cat has pink gums, much like our own.
b). Watch for discolored or frayed fur. The white coat, which is generally a sign of parasites, is also indicative of worms.
c). Look for any flaky or matted fur. If your cat's coat changes, it might indicate it has never been treated with antibiotics.
d). Identify odors caused by worm infections. This is especially important if the worms lay eggs.. The answer should be
a).