For this sentence transition question, we must use our knowledge of punctuation rules to decide which answer choice is correct. We know that semicolons separate two independent clauses, and a comma cannot separate two independent clauses. For those who don’t know, an independent clause is basically a part of a sentence that can be its own full sentence and would still be grammatically correct. Both parts of the sentence (“meanwhile” to “script” and “effective” to project”) are independent clauses, meaning that we must use a semicolon or period here, which eliminates answer choices A and D (a colon is usually used to introduce a list or clarify something). The “but” in choice C would be unnecessary because that part of the sentence is already an independent clause and does not need another word to be added on. B is the correct answer.