Suppose that all the terms of an arithmetic progression ($A.P.$) are natural numbers. If the ratio of the sum of the first seven terms to the sum of the first eleven terms is $6: 11$ and the seventh term lies in between $130$ and $140$ , then the common difference of this $A.P.$ is

  • [IIT 2015]
  • A

    $6$

  • B

    $7$

  • C

    $8$

  • D

    $9$

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