A researcher studying organic compounds has found that five different molecules - T, W, X, Y and Z-form chains According to the following rules :
i) A chain consists of three or more molecules, though the molecules in the chain are not necessarily different.
ii) T is never found on either end of a chain.
iii) If W appears in a chain, it appears more than once.
iv) X is never found next to Y in a chain.
v) W is never found on the end of a chain unless Z is found somewhere in the chain.
vi) If Y appears in a chain, Z appears also.
Which of the following sequences can be converted into a chain by adding Z and rearranging to molecules ?
I. X Y X T
II. W T T Z
III. X X T W

Options

A. I only
B. II only
C. III only
D. I and III only

Answer

A

Explanation

Test of three statements.
I. Adding a Z to this sequence will correct the problem of having a Y without a Z. Then , recording can move T from the end into the interior of the sequence and separate the X and Y:
X Z Y T X
This is a chain.
II. This sequence has a w without a second W and the addition of a Z will not cure that defect.
III. This sequence also has a W without a second W and the addition of a Z will not cure the defect.