B because he knows he can see something when he is almost home
The prophecy from the witches state that no woman born from man shall harm Macbeth. We learn in the story that Macduff was ultimately ripped out of his mothers womb (through a c-section) this means that he was technically actually never born
A "popular press source" in general refers to any news publication, either on paper or online, that has a wide circulation and is popular. Although this doesn't always mean that it is reputable.
The air we breathe that is the answer I believe it's right