Would it make more sense to have two questions, one multiple choice question followed by an open ended question, "why did you select { ... }" ?
You can add (or even require) text entry for a multiple choice response by selecting Allow Text Entry on that choice's dropdown, but two questions seems better to me.

https://www.qualtrics.com/community/discussion/comment/26281#Comment_26281Thanks for the suggestion. So if i have 2 questions as separate, can i still randomize them as a one question. Like, they should randomize together.

The multiple choice question can still have a randomized order if that's what you mean. I'm not following the "randomize them as a one question" part, however. The second question would be open ended and wouldn't be random anything in what I'm picturing. Just a follow up question looking for a single open ended response. Could you elaborate on randomizing the open ended part?

https://www.qualtrics.com/community/discussion/10496/can-i-have-multiple-choice-and-open-ended-question-in-a-same-questionI have the same need for this - an open ended text box to ask the respondents why they selected the above close-ended multiple choice response. I'm not able to use two questions to accomplish this because there is a skip pattern that needs to be followed (e.g., Strongly Disagree and Disagree responses skip the next question).

Have you tried using an in page display logic to accomplish this? Demo.

Hey Christaann !
It sounds like you might want to use Display Logic instead of Skip Logic for your purpose (if you aren't concerned with randomizing). You can ask your multiple choice question (Q1), then ask open-ended response (Q2) and then use display logic for next question (Q3) using Strongly Agree, Agree, etc. displays the question.
Hope this helps,
Sabrina

sharmac
Maybe you could build your question groups (1 multiple choice and 1 open-ended text) in blocks and use the survey flow randomizer? https://www.qualtrics.com/support/survey-platform/survey-module/survey-flow/standard-elements/randomizer/

https://www.qualtrics.com/community/discussion/comment/33974#Comment_33974Thanks SabrinaC! This is what I ended up doing. Thank you!