This question has Statement $1$ and Statement $2.$ Of the four choices given after the Statements,choose the one that best describes the two Statements.
Statement $1:$ In the resonance tube experiment,if the tuning fork is replaced by another identical tuning fork but with its arms filed,the length of the air column should be increased to obtain resonance again.
Statement $2:$ On filing the arms,the frequency of a tuning fork increases.

• A
  Statement $1$ is true,Statement $2$ is true,Statement $2$ is a correct explanation of Statement $1.$
• B
  Statement $1$ is true,Statement $2$ is false.
• C
  Statement $1$ is false,Statement $2$ is true.
• D
  Statement $1$ is true,Statement $2$ is true,Statement $2$ is not a correct explanation of Statement $1.$