To convert milliliters to liters, you divide the number of milliliters by 1,000, since there are 1,000 milliliters in one liter.
So, for 3,200 milliliters:
\[ 3,200 , \text{milliliters} \div 1,000 = 3.2 , \text{liters} \]
The correct answer is 3.2 liters.