Answer: B! hope this helps. :)
Explanation:
the couplet form support the meaning of the lines:
a. by completing the speaker's thought
The answer is B. because this is the only answer that is an immediate call to action for the situation, instead of just telling you facts like the other answers, this answer tells you straight up what you should do.
Scientific knowledge change over time because we discover news things or properties that impacts how things actually work in the science world. What impact these have on society is that it helps us be more aware of the things in our world, apply these newly dicover knowledge into our own lives to make it better, and it is the beginning step to knowing and discovering more about the world that we live in.