The theme of the story is that you need to take time and effort on doing things right because soon it will pay off. When we do something, we need to consider the effects of our decision on the future. Some pigs compromised on time and the materials of their houses hence the quality and their safety were also compromised.
C: suffering often builds character
hope this helps
Even though you didn't give us the fragment with the comma slice, it isn't really necessary here as we can answer just based on these 4 options here. All options apart from the second one are correct - only the second option doesn't fix the mistake of the comma splice, whereas the other options do but connecting the sentences properly.
