Hey there! I'm happy to help!
If something is symmetrical you can cut a line through it and it will be the same on both sides. If you have a perfect circle you can cut it in half and it will be the same on both sides, so it is symmetrical.
We see that W looks the same on both sides if you cut it in half at the 3. It is the same on both sides, so the answer is W.
Have a wonderful day! :D