Which option is a run-on sentence?

I want to eat now.

The experiment was a success my lab group and I were pleased with the results.

Dorien will be painting the mural over the holiday break.

Need help with those paint cans?

The option "The experiment was a success my lab group and I were pleased with the results." is a run-on sentence because it combines two independent clauses ("The experiment was a success" and "my lab group and I were pleased with the results") without proper punctuation or conjunction.