Let $R$ be an equivalence relation defined on $\{-100,-99,$dots,$99,100\}$ by $xRy$ if and only if either $xy>0$ or $x=y=0.$ Which of the following is

true about the equivalence classes of $R?$

Select one:

There are two. One has $101$ elements and one has $100$ elements.

There is one. It has $201$ elements.

There are three. Each has $67$ elements.

There are $201.$ Each has $1$ element.

There are three. Two have $100$ elements and one has $1$ element.