Ark should be able to do the equivalent of "zip --encrypt". Therefore, a checkbox should be added to the GUI to select encryption. A password field or a popup containing that field would be needed, too. 

Reproducible: Always

Steps to Reproduce:
1. open Ark to create a zip file

Actual Results:  
no possibility for encryption present

Expected Results:  
encryption should be selectable

Zip encryption is not necessarily the safest encryption possible (except if AES is used). Nevertheless, it is better than no encryption at all, which often is the alternative.