Correct option is A
Given = BDG, DFI, FHK, HJM, JLO,?

first letters of the given all term -
B - D - F - H - J - ?
Logic = + 2 in each letters
first letter of missing term - J + 2 = L
second letters of the given all term -
D - F - H - J - L - ?
Logic= + 2 in each letters
second letter of missing term - L + 2 = N
Third letters of the given all term -
G - I - K - M - O - ?
Logic= + 2 in each letters
Third letter of missing term - O + 2 = Q
Missing term = LNQ