The equation \(3%(p) + p = 1.03p\) represents the situation of calculating the total amount after adding a 3% tax or fee to an initial amount (\(p\)).
Thus, the correct match is:
D. the amount that Sandy paid for a shirt with 3% tax on p
This is because \(3%(p)\) represents the 3% tax on the original price \(p\), and the equation shows the total amount paid after including the tax.