Using the rules of aromaticity, classify the given ion below as aromatic, antiaromatic, or nonaromatic. If classified as aromatic/antiaromatic, determine the value of n in Hückel's/Breslow's rule. If classified as nonaromatic, provide an explanation.

• A. The ion is aromatic, and n = 1. 
• B. The ion is aromatic, and n = 2. 
• C. The ion is antiaromatic, and n = 1. 
• D. The ion is antiaromatic, and n = 2. 
• E. The ion is nonaromatic because it not planar.

Answer: (D)