Statements:
W @ F, F S M, M © D
Conclusions:
I. D S F II. W © B III. F S D

Correct Answer: Only either I or II and III are true

Explanation:

M ? W ...(i) W = N ...(ii) N > B ...(iii)
Combining these we get M ? W = N > B.
Hence M ? N or N ? M,
Which means either I (N = M) or II (N < M) follows.
Also M > B and II (M ? D) Hence III deficitely true.

Correct Answer: Only either I or II and III are true

Explanation:

M ? W ...(i) W = N ...(ii) N > B ...(iii)
Combining these we get M ? W = N > B.
Hence M ? N or N ? M,
Which means either I (N = M) or II (N < M) follows.
Also M > B and II (M ? D) Hence III definitely true.

Correct Answer: None is true

Explanation:

R < F ...(i) F ? D ...(ii) D ? M ...(iii)
From (i) and (ii) R and D can't be compared. Hence neight I nor III follows.
From (ii) and (iii) M and F can't be compared. Hence II does not follows.

Correct Answer: if only conclusion II is true

Explanation:

N < O ? R > T; R < A; B ? T
Check for I:
N < O ? R > T
? No definite relation can be found between N and A.
Check for II:

Correct Answer: if neither conclusion I nor II is true

Explanation:

C ? D = E ? F, Y < D ? W
Check for I:
C ? D > Y
It means C > Y. Thus, I does stand true. check for II:
Y < D ? F
It means F > Y. Thus, II also does not stand true.

Correct Answer: Only III is true

Explanation:

B = H ...(i) H > E ...(ii) E ? K ...(iii)
From (i) and (ii) B = H > E or E < B
Hence III follows.
From (ii) and (iii) H and K can't be compared.
Hence I does not follow. Nor can II follow.

Correct Answer: Only II is true

Explanation:

F ? N ...(i) N < D ...(ii) D ? R ...(iii)
From (i) and (ii) F and can't be compared.
Hence I does not follow.
From (ii) and (iii) N < D ? R or R > N ...(iv)
Hence II follows. From (i) and (iv) R and F can't be compared. Hence III does not follow.

Correct Answer: Only I and III are true

Explanation:

F ? B ...(i) B = H ...(ii) H ? K ... (iii)
From (i) B F. Hence I follows.
From (ii) and (iii) B = H ? K or B ? K or K ? B can't be compared. Hence II does not follow.

Correct Answer: Only II is true

Explanation:

M ? D ...(i) D< K ...(ii) K ? N ...(iii)
From (i) and (ii) K and M can't be compared.
Hence I does not follow.
From (ii) and (iii) D < K ? N or N > D.
Hence II follows. From (i) and II, M and N can't be compared. Hence III does not follow.

Correct Answer: if only conclusion II is true

Explanation:

R ? N ...(i) N ? F ...(ii) F > B ...(iii)
From (i) and (ii) F and R can't be compared. Hence I does not follow.
Combing (ii) and (iii) we get N ? F > B or N > B or B < N. Hence II follows.