What should come in place of ‘?’ in the given series?
115, 119, 127, 139, 155, ?

The correct option is 175.

To find the missing term in the given number series, let us analyze the pattern by calculating the differences between consecutive terms:

$119-115=4$

$127-119=8$

$139-127=12$

$155-139=16$

The differences between consecutive terms are 4, 8, 12, and 16. These values are consecutive multiples of 4:

$4\times 1=4$

$4\times 2=8$

$4\times 3=12$

$4\times 4=16$

Following this pattern, the next difference in the series must be the fifth multiple of 4:

$4\times 5=20$

To determine the missing term (?), we add this difference of 20 to the fifth term (155):

$155+20=175$