Answer:
The best revision for the paragraph is to change “having” to “permitting.”
Step-by-step explanation:
If we make each one of the changes that are suggested in the options the only one who makes the text more logic is the first one, since permitting is a more formal word that is also linked to the decision of many schools of not allowing cellphones in the classroom, the other options are not correct because changing those word would change the intention of the paragraph.