You forgot the options!
but let's assume that these could be the options, as posted before
A. stone's throw
B. men's plans
C. it's place
D. women's plans
maybe it will help if i discuss those: A, C, and D are not plural possessive: for this the noun has to be in plural.
In contrast, B: "men" is a plural noun. This is also the correct option. So for a plural possessive, the noun itself needs to be in plural.
hope this helped! if you want, comment with your options and i will comment back.