Explanation Given that W and X is 2

W ------ 2 --------X

Also distance between X and Y is 4,

Case 1 W ------ 2 --------X

.................. X ---------- 4 ----------- Y

Case 2............ W ------ 2 --------X

......Y ---------- 4 ----------- X

Finally, distance between Y and Z is 9

Case 1 W ------ 2 --------X

.................. X ---------- 4 ----------- Y

...............................................Y ------------- 9 -------------- Z

So XZ = 13.Case 2 W ------ 2 --------X

.................. X ---------- 4 ----------- Y

...... .......Z ------------- 9 -------------- Y

So XZ = 5.Case 3 ............ W ------ 2 --------X

......Y ---------- 4 ----------- X

......Y ------------- 9 -------------- Z

So XZ = 5.Case 4 ....................................... W ------ 2 --------X

.................................Y ---------- 4 ----------- X

Z ------------- 9 -------------- Y

So XZ = 13.Hence option B s correct.
_________________

Sandy

If you found this post useful, please let me know by pressing the Kudos Button

Try our free Online GRE Test