The five $P-F$ bond lengths in $PF_5$ are equal whereas the $P-Cl$ bond lengths in $PCl_5$ are not equal because

• A
  $PF_5$ has equivalent hybridization whereas $PCl_5$ has non-equivalent hybridization
• B
  Pseudorotation is observed in $PF_5$ but not in $PCl_5$
• C
  Pseudorotation is observed in $PCl_5$ but not in $PF_5$
• D
  The given statement is wrong and both $PF_5$ and $PCl_5$ have unequal bond lengths