A run-on sentence is a sentence having two independent clauses with improper punctuation and without conjunctions. The correct answer is option b. It is difficult to understand a run-on sentence because you cannot identify where to pause or stop and that the sentence does not have conjunctions which would help in the transition of clauses.
I am not very sure but I would probably use on the other hand or therefore.
List that sorts information based on topic, color, size, etc;
