According to Robin Ryan in the book "60 Seconds and you're Hired" you can honestly say no to this question. Regardless of it you were laid off, fired, or chose to quit for whatever reason you were still presented with the option to leave and you chose to leave.
Too many lawsuits have been initiated over this issue. Your former employer would not likely admit to forcing you out Therefore, honestly say "no."
Now that you have the answer to this question you can also apply this information to completing job applications as well.
Happy Hunting Sarasota!