Which of the following is incorrect for the complex $[Fe(CO)_x]$?

• A
  It is an organometallic compound containing $\sigma$- and $\pi$-bonds.
• B
  The value of $x$ in this complex is $6$.
• C
  In the complex,$CO$ is a $\pi$-acid ligand.
• D
  It has a trigonal bipyramidal geometry.