Freemium Model Monetization Research

Hi, I'm doing a little research for part to complete my thesis and hope you don't mind for helping me. Below here, is a questionnaire about freemium model on mobile gaming. The purpose of this questionnaire is to summarize what's the 'best' combination of freemium aspect that people think will be reasonable to be used in free-to-play game.
The result will be published in public once it's got at least 100 respondents.

I believe that the result will be much helpful for indie developers too to find out the best monetization model if they decide to go with freemium model.
Thank you so much.

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