GKFix MCQ Question

What is the main reason for the difference in reactivity between fluorine and iodine?

• A. Iodine is a solid and fluorine is a gas
• B. Fluorine is lighter than iodine
• C. Fluorine's small atomic size and very high electronegativity make it much more reactive than iodine
• D. Iodine has a filled d-subshell