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

How to make your gerbil happy
Consider getting two same sex gerbils and not just one.
Gerbils are very social creatures and like to live with other gerbils. When first buying your gerbil you should consider getting more than one.

Choose from:
a). This provides more variety to your gerbil's cage. It also provides a much better environment for fighting over food.
b). Whatever your preferences are, consider keeping two or more gerbils and changing some of them every couple of months. Keeping your gerbils and kittens together and not just one is also right.
c). This will keep your gerbil much happier. However, if you already have a gerbil (s) and introduce a new one, it is likely that they will fight.
d). Getting two different gerbils will require more time and money so plan accordingly. In order to ensure you get one gerbil you'll need to determine how much per gerbil you want to convert and/or split your own gerbil's tank.
c).