The answer is the first one
All these sentences use the word "so" correctly except "Flies breathe through holes in
<span> their abdomen or thorax, so do bees.</span>" So should either begin a new sentence of be preceded by "and".
Answer:
Is not always directly stated
C. Just had this question myself
With the A. migration of people from fertile areas, knowledge of agriculture spread by diffusion.
When people migrate from a place, they move into other areas. When something diffuses, it spreads around.
