The correct answer is $\boxed{\text{B. }\$6,450}$.
Direct service labor is the cost of labor that is directly attributable to the production of a good or service. Idle time wages are the wages paid to employees who are not working because there is no work for them to do. Overtime premium is the additional pay that employees receive for working more than the standard number of hours.
To calculate the total figure, we need to add the direct service labor, idle time wages, and overtime premium. Direct service labor + idle time wages + overtime premium = $5,000 + $1,000 + $450 = $6,450.
Option A is incorrect because it does not include the overtime premium. Option C is incorrect because it is the sum of the direct service labor and idle time wages, but it does not include the overtime premium. Option D is incorrect because it is the sum of the direct service labor, idle time wages, and overtime premium, but it is multiplied by 2.