Verbal Reasoning - Mental Ability Questions

C is D's daughter and D is B's son. So, D is the brother of C. E is a male married to C. 

So, E is the husband of C, whose brother is D. So, D is the brother-in-law of E. 

From both the statements together, we find that Tarun's father has three children — Tarun and his two sisters This means that Tarun has no brother.

So, both I and II are needed. 

The root nodules of leguminous plants contain certain nitrogen fixing bacteria which absorb the atmospheric nitrogen and convert it into nitrogeneous compounds useful for the plants reviving soil fertility. 

The given sequence a combination of two series:
I)Z, W, T, Q, ?      and      II)S, O, K, G, ?

The pattern I is
Z - 3 = W
W - 3 = T
T - 3 = Q
Q - 3 = N

The pattern in II is
S - 4 = O
O - 4 = K
K - 4 = G
G - 4 = C

If each consecutive letter in "happiness" relates to the consecutive numbers in 517768399, then H=5, A=1, P=7, I=6, N=8, E=3 and S=9.

Using the numbers that relate to the letters in 'senipah', you will arrive at

SENIPAH = 9386715.

Hence, Happiness is to 517768399 as senipah is to 9386715.