Which of the following compounds has the smallest bond angle $(X - A - X)$ in each series respectively?
$(A) \ OSF_2 \ \ \ \ \ \ \ \ \ OSCl_2 \ \ \ \ \ \ \ \ \ OSBr_2$
$(B) \ SbCl_3 \ \ \ \ \ \ \ \ \ SbBr_3 \ \ \ \ \ \ \ \ \ SbI_3$
$(C) \ PI_3 \ \ \ \ \ \ \ \ \ \ \ \ AsI_3 \ \ \ \ \ \ \ \ \ \ \ \ SbI_3$

• A
  $OSF_2, SbCl_3$ and $PI_3$
• B
  $OSBr_2, SbI_3$ and $PI_3$
• C
  $OSF_2, SbI_3$ and $PI_3$
• D
  $OSF_2, SbCl_3$ and $SbI_3$