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

How to get rid of mice fast 
Keep your food sources in metal or glass containers with secure lids. 
Mice can eat through cardboard, certain plastics, and other forms of containers to get at food. In order to cut down the mice's food supply, make sure that you don't leave any food out, or if you do, to put it in something that mice cannot get at.

OPT: a. Make sure the glass container holds enough food that mice cannot eat through it. When you write down how much food you are putting out, it will be easier to keep track.. b. Ideally, a bucket lid or glass container should also come with very secure lids. Avoid shaking the container when putting food inside.. c. Cover food sources and objects on your fridge and freezer shelves. Doing this will keep mice away and help your food supply last longer.. d. Don't leave out pet food. Remove any food that your pet hasn't eaten immediately after its meal..
d.