If the ${n^{th}}$ term of an $A.P.$ is $(2n - 1)$,then the sum of its first $n$ terms will be

  • A
    ${n^2} - 1$
  • B
    ${(2n - 1)^2}$
  • C
    ${n^2}$
  • D
    ${n^2} + 1$

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