A sequence a, ax, ax2, _______ axn, has odd number of terms. Then the median is
1
\({\rm{a}}{{\rm{x}}^{\frac{{\rm{n}}}{2} + 1}}\)
2
\({\rm{a}}{{\rm{x}}^{\frac{{\rm{n}}}{2} - 1}}\)
3
\({\rm{a}}{{\rm{x}}^{{\rm{n}} - 1}}\)
4
\({\rm{a}}{{\rm{x}}^{\frac{{\rm{n}}}{2}}}\)