Correct Answer: JUKLKWJ

Solution : Given:
LTK_HL_ _JH_V_JHL_K_H

To fill the series we have to divide the series – LTK_H / L_ _JH / _V_JH / L_K_H

Let's check each option –
First option: JUKLKWJ ; LTK J H / L UK JH / L V K JH / L W K J H (The second letter of each part increases by 1; LKJH is repeated in the series)
Second option: IUKLKWJ ; LTK I H / L UK JH / L V K JH / L W K J H (No repeated pattern has been found)
Third option: IUKMKWJ ; LTK I H / L UK JH / M V K JH / L W K J H (No repeated pattern has been found)
Fourth option: JUKLKXJ ; LTK J H / L UK JH / L V K JH / L X K J H (No repeated pattern has been found)

So, the series becomes→LTKJHLUKJHLVKJHLWKJH. Hence, the first option is correct.