Correct option is B
In this series,
XO, CJ, HF, MC, RA
Place value of first letter of first term increased by 5 in each term where as the place value of second letter decreased by 5,4,3,2
That is
XO-Place value of X= 24 adding 5 to this we get the first letter of the next term that is C
Place value of O = 15 subtracting 5 we get place value of Second letter of the next term that is J.