After arranging the given words according to dictionary order, which word will come at 'Third' position?
1. Region
2. Register
3. Regim
4. Regional
5. Regimen​​

Given:
1. Region
2. Register
3. Regim
4. Regional
5. Regimen

Let's arrange the given words in dictionary order:
3. Regim (R-e-g-i-m)
5. Regimen (R-e-g-i-m-e-n)
1. Region (R-e-g-i-o-n)
4. Regional (R-e-g-i-o-n-a-l)
2. Register (R-e-g-i-s-t-e-r)
So, the Third position word is Region.
Thus, the correct option is: (b)