18. Which arithmetic sequence has a common difference of 4? A. (0,4n, 8n, 12n, ...} B. (n, 4n, 16n, 64n, .} C. (n + 1, n+ 5, n+9, n+ 13, ...} D. (n + 4, n+ 16, n+ 64, n+ 256, .}