If $\theta$ is the interior angle of a regular pentagon,then $|(\sin \theta) \hat{i}+(\cos \theta) \hat{j}+(\tan \theta) \hat{k}|=$

  • A
    $|\sec 18^{\circ}|$
  • B
    $|\operatorname{cosec} 18^{\circ}|$
  • C
    $-\sec 18^{\circ}$
  • D
    $\operatorname{cosec} 108^{\circ}$

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