The answer is D: The band trip is almost full, so if the color guard members want to go, they will need to sign up soon.
Their is no man in the bake sale sentence. Hence, him. Same for the other sentences.
Because of this, our critical thinking skills are being enhanced. When we practice causal analysis, we do not only identify what happened, but instead, we are compelled to dig deeper and learn what caused an event to happen.
Even though you did say never mind, I would say a bit of both. Both together make a good leader.