In the given diagrams, there is a pattern that can be observed. In the first row, the values are increasing by 16 each time: 20, 36, 52. In the second row, the values are increasing by 18 each time: 30, 48, 66.

In the third row, the values are increasing by 6 each time: 25, 31, 37. In the fourth row, the values are increasing by 10 each time: 7, 17, 27.

Based on this pattern, we can deduce that the missing number should be 37 + 6 = 43. Therefore, option 3 is the correct answer.

Alert - correct answer should be option 3.