Which sentence is a run-on sentence? A. Ostrich eggs are huge and weigh about three pounds each. B. Pigs are intelligent they can be taught tricks. C. Coyotes are nomads; they usually travel alone. D. Opossums move very slowly and can be caught easily.

Answer :

B, pigs are intelligent... the others seem to run on, but have conjunctions
B. Pigs are intelligent they can be taught tricks. There are two sentences that aren't joined with conjunctions or semicolons.
It would be a sentence if they said, " Pigs are intelligent and they can be taught tricks"