Why colonial organisms that lived grouped together might have been one of the first steps toward multicellular organisms in the
course of evolution

Colonial organisms are the result of many identical individuals joining together to form a colony. These cells are partly dependent on each other to start with. But, later evolutionary events resulted in the obligatory relationships among them resulted in multicellularity.

what statement best describes the difference between the sympathetic and parasympathetic nervous systems?

the sympathetic nervous system prepares the body for intense physical activity and is often referred to as the fight-or-flight response. the parasympathetic nervous system has almost the exact opposite effect and relaxes the body and inhibits or slows many high energy functions.

you didn't give any options but heres what i can tell you: an inference is likely to change based on additional observations. the latter is something that you have seen or sensed using your sensory organs while the former is like a conclusion out from what you have observed.