If the ${n^{th}}$ term of an $A.P.$ be $(2n - 1)$, 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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