Answer:
The amount financed under this mortgage is $180,000
B is correct. 
Explanation:
Larry took out an 80/20 mortgage on a $225,000 home.
80/20 mortgage means pay 20% down payment and 80% finance amount of home value. 
Home value = $225,000 
Here, we need to find finance amount from $225,000
We will calculate the 80% of $225,000
Finance amount = 80% of 22500
 = 0.80 x 225000
 = 180000
Hence, The amount financed under this mortgage is $180,000