To find the percentage of tax on the chicken sandwich, you can use the formula:
\[ \text{Tax Percentage} = \left(\frac{\text{Tax Amount}}{\text{Original Price}}\right) \times 100 \]
In this case, the tax amount is $0.27 and the original price is $4.50.
Calculating the tax percentage:
\[ \text{Tax Percentage} = \left(\frac{0.27}{4.50}\right) \times 100 \]
\[ \text{Tax Percentage} = \left(0.06\right) \times 100 = 6% \]
So, the percentage of tax is 6% (A).