16 26 56 36 46 68 56

• A. 64 82
• B. 78 68
• C. 66 80
• D. 66 82
• E. 80 66

Answer: (C)

Here, every third number follows a different pattern from the main series. In the main series, beginning with 16, 10 is added to each number to arrive at the next. In the alternating series, beginning with 56, 12 is added to each number to arrive at the next.