Three objects are brought together, two at a time. A is brought near B and they repel. B is then brought to C and they repel. Which of the following is true?
a)A and C have the same sign
b) A and C have opposite sign
c)A, B, and C have the same sign
d)One of them is neutral
e)Need additional experiment to determine the signs
I picked c) and it says it is a), why?