Final answer:
The correct revision to add commas to the sentence is option c.
Step-by-step explanation:
The correct revision that adds commas to the sentence is option c. The revised sentence would be: 'From smartphones, to tablets, to laptops, modern technology is mobile, easy-to-use, and everywhere.' Commas are used to separate the different items in a list, which in this case are smartphones, tablets, and laptops.
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