Among the following,the crystal system which includes end-centered is

• A
  $a=b=c$ and $\alpha=\beta=\gamma=90^{\circ}$
• B
  $a=b \neq c$ and $\alpha=\beta=\gamma=90^{\circ}$
• C
  $a \neq b \neq c$ and $\alpha=\beta=\gamma=90^{\circ}$
• D
  $a=b=c$ and $\alpha=\beta=\gamma \neq 90^{\circ}$