In each of the following questions, a specific pattern such as reversal or rearrangement has been applied to the first word to get the second. Apply the same pattern to the third word and find the correct answer from the given options.
ETAGIROV : VORIGATE :: GNITSET : ?

The correct option is TESTING.

Step 1: Analyze the pattern in the first word pair
Let us compare the first word "ETAGIROV" with the second word "VORIGATE":
If we reverse the letters of the word "ETAGIROV", we get:
E - T - A - G - I - R - O - V  ⇒  V - O - R - I - G - A - T - E (which spells "VORIGATE").
Thus, the transformation rule is simply reversing the order of all the letters in the word.

Step 2: Apply the same pattern to the third word
Now, apply the reversal rule to the third word "GNITSET":
Reversing the letters of "GNITSET" step-by-step from last to first:
1^st letter: T
2^nd letter: E
3^rd letter: S
4^th letter: T
5^th letter: I
6^th letter: N
7^th letter: G
Combining these gives the word "TESTING".

Therefore, the correct missing word is TESTING.