Verbal Reasoning - Mental Ability Questions

Select the related word/letters/number from the given alternatives.
EFGH: LNPR : : ABCD : ?

If X's mother is the only daughter of Y's father, then Y's husband 's father is X's ___.

Select the related word/letters/number from the given alternatives. AIDS : VIRUS : : MALARIA : ?

If in a code language 3456 = ROPE and 15526 = APPLE then 54613 = ?

A series is given with one term missing. Select the correct alternative from the given ones that will complete the series. CX, EV, GT, IR, ?

A series is given with one term missing. Select the correct alternative from the given ones that will complete the series.

Q, P, O, N, ?

In a certain code language, “MAKER” is written as “PDNHU”. How is “TOOLS” written in that code language?

A series is given with one term missing. Choose the correct alternative from the given ones that will complete the series.
MN, PQ, TU, YZ, ?