Backblaze B2 backup query

[kashif789us]

Hi. I have linked Backblaze B2 to my Qnap NAS via Hybrid Backup Sync 3.

I am backing up 3 macs to my NAS. I am now backing up these 3 drives to B2.

I have few questions:
1. I selected Backup not Sync in HBS3. Is this correct? Or should I select sync?
2. I also selected to delete data in destination when deleted in source. Is this correct?
3. While setting up backup, I encrypted the data as well as enabled QuDudep. Is this okay?
4. Data is still being uploaded. When I browse it on Backblaze dashboard, it does not show a sparsebundle file. Instead it's showing some encrypted type of data. Is this fine? If I have to restore it, I will be able to get .sparsebundle without any problem? Correct?