How to name variables in the operation queue?

1 – Don’t change the variable name:

 function example($  array)  {      $  array = array_unique($  array);      $  array = array_reverse($  array);      $  array = array_map(function($  value) { return 'x'.$  value; }, $  array);       return $  array;  }  

2 – Change the name of the variable to associated with the method:

 function example($  array)  {      $  arrayUnique = array_unique($  array);      $  arrayReverse = array_reverse($  arrayUnique);      $  arrayMap = array_map(function($  value) { return 'x'.$  value; }, $  arrayReverse);       return $  arrayMap;  }  

3 – Change the name of the variable to associated with the operation:

 function example($  array)  {      $  arrayRemovedDuplicates = array_unique($  array);      $  arrayReverse = array_reverse($  arrayRemovedDuplicates);      $  arrayAddPrefixX = array_map(function($  value) { return 'x'.$  value; }, $  arrayReverse);       return $  arrayAddPrefixX;  }  

4 – other?