You can assign employees in two different ways:

(i) 3 employees to one office and 0 to the other office.
(ii) 2 employees to one office and 1 to the other office.

For (i), You can put the employees on the 1st or 2nd office, those are two ways of arranging the employees.

For (ii) you have to consider the possible combinations of 2 from 3 = 3!/2!(3-2)! = 3. And you can assign those possible combinations to office 1 or 2, therefore you have 6 possible ways of assigning the employees.

So we have a total of 8 ways of assigning employees.

(D)

This is how it goes:

1 way: Emp1 Emp2 Emp3
2 way: Emp3 Emp1 Emp2

3 way: Emp1 Emp3 Emp2
4 way: Emp2 Emp1 Emp3

5 way: Emp3 Emp2 Emp1
6 way: Emp1 Emp3 Emp2

7 way: Emp1 Emp2 Emp3. No body on the other office.
8 way: No boby in the first and all 3 in the second.

bold: Office 1

unbold: Office 2

thanks guys!