The rule of housing often suggests that your monthly housing budget should not exceed 30% of your gross monthly income.
First, let's calculate Harper's gross monthly income:
\[ \text{Monthly Salary} = \frac{\text{Annual Salary}}{12} = \frac{60,000}{12} = 5,000 \]
Now, we calculate 30% of her monthly salary to determine her housing budget:
\[ \text{Housing Budget} = 0.30 \times \text{Monthly Salary} = 0.30 \times 5,000 = 1,500 \]
Since $1,500 is not one of the options provided, and if we round down to the closest option, Harper's housing budget would correspond to $1,250.
So, the correct response from the available choices would be $1,250.