Sodium and aluminum are in the same period, and therefore have similar chemical properties. It's B.
I think this is classified as a Idiom
Answer:
It is important so you have an idea what write about.
Explanation:
B: Set the mood for the scene that follows.
The author is obviously trying to set something up to happen here, most likely the entrance of another character and/or some dialogue. It would't make sense for there to bee any foreshadowing with such a warm atmosphere, and the author is describing the setting, not the characters.
