To find the estimated cost for 4.5 pounds of cucumbers, you can multiply the cost per pound of cucumbers by the number of pounds.
The cost per pound of cucumbers is $2.59.
So, the calculation would be:
\[ 4.5 , \text{pounds} \times 2.59 , \text{dollars/pound} = 11.655 , \text{dollars} \]
Rounding to the nearest whole number, the estimated cost is approximately $12.
Since none of the given options match the calculated result, it seems that the closest reasonable estimate from the provided choices would be $10. However, none are accurate; the exact answer is not listed among the options.