PART B: What does this sentence suggest about the deaths described in the passage?

“No one knew that a killer was already moving through their streets with them, an invisible stalker that would go house to house until it had touched everyone, rich or poor, in some terrible way.”

a. Citizens were terrified because there would be more deaths.
b. The deaths were caused by a criminal who could hide himself.
c. Everyone was going to die, except for the richest citizens.
d. All the deaths had the same cause, and everyone would be affected.