15. Assume that and take distinct equidistant positions from the median of a symmetric distribution (not necessarily unimodal), with half the voters between the announced policy positions of and . Which of the following statements is true?
The 1/3-separation obstacle applies.
The 2/3-separation opportunity applies.
Neither the 1/3-separation obstacle nor the 2/3-separation opportunity applies.
Both the 1/3-separation obstacle and the 2/3-separation opportunity apply.