Which simpler problems could be calculated to solve this problem?

nick bought 3 new t-shirts for $12.99 each. sunscreen was on sale at 3 bottles for $15, and nick bought one bottle. nick had to pay $4.39 sales tax on the items. how much money did nick spend altogether?

a.
multiply the cost of one t-shirt by 3.
calculate the cost of one bottle of sunscreen.
calculate the cost of the t-shirts and sunscreen.

b.
calculate the cost of one bottle of sunscreen.
calculate the total cost of the t-shirts.
calculate the cost of the sunscreen and the t-shirts plus the tax.

c.
add the cost of three t-shirts to $15.
divide by 3.
calculate the cost of the items plus the tax.