In certain polar solvents, PCl₅ undergoes an ionization reaction in which a Cl⁻ ion leaves one PCl₅ molecule and attaches itself to another. The products of the ionization are PCl₄⁺ and PCl₆⁻. How do the P−Cl single bond lengths in PCl₅, PCl₄⁺, and PCl₆⁻ generally compare?
A. PCl₅ < PCl₄⁺ < PCl₆⁻
B. PCl₅ < PCl₆⁻ < PCl₄⁺
C. PCl₅ = PCl₄⁺ = PCl₆⁻
D. PCl₆⁻ < PCl₄⁺ < PCl₅
E. PCl₄⁺ = PCl₆⁻ < PCl₅