The moulting hormone in insects is secreted by which

Select the option that is related to the third number in the same way as the second number is related to the first number.

223 : 350 :: 519 : ?

Select the option in which the letters share the same relationship as that shared by the given pair of letters. 

LV : PZ

‘Confined spaces’ is related to ‘Claustrophobia’ in the same way as ‘Insects’ is related to ‘______’.

Select the option that is related to third number cluster in the same way second number cluster is related to first number cluster.

14: 168 :: 21: ?

Select the option in which the numbers are related in the same way as are the numbers of the following sets.  

(11, 13, 72)