You can set this up easily by applying a workaround with Contact Custom fields in
Global Data (learn more about custom contact fields).
Important note
it's advisable to create and manage all custom fields in 
Tracking menu, from where you will be able to see all of the custom fields created, which will help you avoid creating duplicates
This additional menu helps you with full overview of all created contact custom fields, ensures you're not adding duplicates, which will keep your analytics precise.
Tracking menu is available for Business and Enterprise subscription plans
(see detailed pricing and feature breakdown here).
Navigate to Global Data → Contacts section
Scroll to the far right to "Add column" and initiate Custom Contact field builder
Select field type
This case required a user to choose only one of predefined set of mutually exclusive options
In case you need multiple options available, choose Checkbox type
(learn more about Contact custom field formats)
Enter field name, select color for easier visual identification of the answer, and add name the options
Confirm by clicking on "Add field" button
Your new column will appear in Global Data → Contacts section, and now you will be able to fill them out, by selecting options by clicking on the "Pencil/Ddit" button inside every cell.
This specific case is good for tagging disqualified leads in more detail. Some leads will be permanently disqualified, meaning that we don't want to revisit them (e.g. lead who is no longer an entrepreneur).
On the other hand, others may be tagged as disqualified today, but worth revisiting in the future. (Typically it is a too low turnover, but still it may be worth of effort).