The correct option is B 28G
The letters in the first row form a series C, D and E (a series of consecutive letters). The letters in the second row form a series I, K and M (a series of alternate letters). Similarly, the letters in the third row will form the series D, G and J (a series in which each letter is 3 steps ahead of the previous one). So, the missing letter is G.
Also, the number in the second column in equal to the product of the numbers in the first and third columns. So, missing number is 4 X 7 i.e., 28. Thus the answer is 28G.
Hence, option (B) is the correct answer.