GMAT Sentence Correction (SC) | Micheaux contends that the guild system both limited and encouraged ex

I had difficulty in reading the ques


Micheaux contends that artisans.....were allowed.... , yet.. they were...--sentence is correct

But I thought this part as a fragment-- "the guild system both limited and encouraged experimentation in Renaissance Italy :"

Expert, please explain how this phrase("the guild system both limited and encouraged experimentation in Renaissance Italy :") is put in this sentence. I might not know what is the usage of ":"

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