> For the complete documentation index, see [llms.txt](https://help.dscout.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.dscout.com/study-basics/design-a-mission/must-select-logic.md).
# Must select logic
| Study type | Availability |
|---|
| Screeners | true |
| Usability tests | true |
| Media surveys | true |
| Intercept studies | true |
**Must-select can be set on Multiple Select questions.** Use this logic to designate response choices participants must select to qualify.
All choices pre-populate as ‘May Select’, which means that participants may select that answer choice to continue. If participants must select an answer choice to continue, or if participants should be knocked out for selecting an answer choice, click on the arrow in the box next to that answer choice to change the applied logic. You can designate ‘Must Select’, ‘May Select’, and ‘Knockout’, and logic must be applied to all answer choices.
{% hint style="info" %}
**Note:** Knockout logic takes priority and will disqualify participants (in the example below, someone who chooses "French press" *and* "Drip coffee maker" will still be disqualified).
{% endhint %}
Per your selection, participants must choose at least one OR all must-select choices to qualify. Logic doesn’t need to be applied to all choices.
---
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