Paint costs $3.99 per can and brushes cost $2.50 each. The sales tax rate is 5%. Which expression represents the total cost of p cans of paint and b paint brushes?A. 3.99p + 2.50bB. 0.05(3.99p + 2.50b)C. 1.05(3.99p + 2.50b)D. –1.05(3.99p + 2.50b)

The answer is C. 
This is because choice A does not include the tax, B is the tax rate for the items themselves but does not account for the actual price of the items, and D is just wrong. The only answer remaining is C.