Which of the following statements is wrong?

• A
  In $2-$methyl$-1,3-$butadiene,the bond length $\ell_2 > \ell_1$.
• B
  In the tropylium cation $(C_7H_7^+)$,the bond lengths $\ell_1 = \ell_2$.
• C
  In pyridine,the bond lengths $\ell_1 = \ell_2$.
• D
  In cyclooctatetraene,the bond lengths $\ell_1 = \ell_2$.