If he were here, it could be more fun This statement was referring to a third singular person. This means that, the event was fun. But the fun could have been more if that person was present. ''It could'' as used in the statement is a probability. There is no assurance that the presence of that particular person would bring more fun. Option A is the correct option. He did not show up and so the occasion lacked much fun Meaning there was fun, but it wasn't much fun because he wasn't present.