Answer is bottom front teeth
Reason
Firstly, this area is a difficult spot to clean, especially if the head of your toothbrush is bulky. It is very easy to skim over, leaving plaque behind. Also, there are saliva ducts present on the floor of the mouth, adjacent to these teeth, so saliva is continually bathing this area.
The answer would be false
Yes, there is a variety of things you can do to wear down the enamel. A few of the biggest things are: Drinking Coffee or soda, eating acidic foods and not brushing your teeth. Sadly you are not able to grow back your enamel after if it fully gone so it's best to protect your enamel as much as possible.