@Atoosa0 you can Accept or Decline a reservation request, not an inquiry since the guest is only asking questions. When you get a reservation request, Airbnb will provide you with the guests' profile. Click on the picture and you will see what kind of identification the guest has provided. The highest amount of identification will result in a Verified ID badge similar to the one you have.
Here's what I typically do:
1. I have set as a Reservation Requirement that all guest have Verified ID. Go to Manage Listing and to the left of your listing picture you will see Reservation Requirements. Click on it and select Verified ID.
2. I ask the requesting guest what the reason is for their stay and otherwise ask questions to see if they make sense. I had a reservation request recently where the guest told me he planned to visit an area 100's of miles from where I am located so that was obviously a bad fit. When I told him that, he thanked me for letting him know and cancelled the request.
3. I ask guests to read and confirm that they agree to my house rules before I accept their request. That way there are no misunderstandings on what I allow. I didn't look at yours, but hopefully you have a comprehensive list.
4. I look at their reviews if they have them. I often host guests without reviews as they are new to Airbnb and all have been great.
A friend of mine who I consider an expert in hosting put together a list of red flags concerning guests that you might read:
http://globalhosting.freeforums.net/thread/455/red-flags-hosts
After you have more guests, your intuition will guide you.
PS: in your lisiting title you say "quite" It should be spelled "quiet" 🙂
Hope this helps!