Select the option that is related to the fourth term in the same way as the first term is related to the second term and the fifth term is related to the sixth term.

18 : 234 :: ? : 176 :: 14 : 126

16

Pattern followed here is :

2nd number =  (1stnumber)² -  (1st number × 5 )

Apply this pattern to given series :

18 : 234

2nd number =  (18)² -  (18 × 5 )

= 324 - 90

= 234

&   14 : 126

2nd number =  (14)² -  (14 × 5 )

= 196 - 70

= 126

Similarly ,

? : 176

176 =  (X)² -  (X × 5 )

 (X)² -  (X × 5 ) - 176 = 0

On solving ,

X = 16

16 is correct answer .