To calculate the income tax, you multiply the amount by the tax rate.
For 400 Naira at the rate of \( \frac{2}{2} \) kobo per Naira (which is equivalent to \( \frac{1}{100} \) Naira per Naira), the income tax would be:
\[ \text{Income Tax} = 400 \times \frac{1}{100} \]
\[ \text{Income Tax} = 4 \, \text{Naira} \]
So, the correct option is B. 4 Naira.
