If Diego wanted to find out how many people prefer emails on their smartphones or tablets, he would most likely engage in qualitative research with the use of questionnaires.
This refers to the statistical findings that is done about a particular area of study to find out more about it.
Hence, we can see that because Diego works for an electronics firm and wants to find out how many people prefer to reply to emails through their smartphones or tablets, he would most likely engage in qualitative research with the use of questionnaires.
Read more about questionnaires here:
https://brainly.com/question/14610641
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