Qualtrics Matrix Side by Side: Only Record Final Click

Question

I have a qualtrics side-by-side question with 10 statements and two columns. By default, Qualtrics has the respondent pick one of the two columns in each row. However, I only want Qualtrics to record the final click across the entire question - e.g. I only want Qualtrics to record the answer for a single row, and leave all other rows blank.

For example, if the question were:

Question:

S1: A or B

S2: A or B

S3: A or B

And the respondent first clicks A in S1, then clicks B in S3 then submits the page, I want Qualtrics to forget what the respondent clicked for S1 - it should only record that the final click across the entire question was B in S3, and record nan values for S1 and S2.