Key driver analysis on customer satisfaction (CSAT)

I have following data from a survey:

1) Customer satisfaction scores (scale 0-10)

2) Indication of which 3 service aspects respondents give highest priority (checkbox question where respondents can select up to 3 out of 14 options)

What is the most appropriate statistical method for this dataset to perform:

1) key driver analysis (which items have most impact on the CSAT result)
2) root cause analysis (which items are indispensable for a high CSAT score)

Many thanks for your ideas!