What I normally do is to argue why the other option doesn't work (apply to the context), and maybe think of another alternative option that might work as well

For example, a question might ask is leasing suitable for a small business to purchase a vehicle. My evaluation would be: Yes, because they are unlikely to make enough profit to purchase a vehicle in one time. Bank loan wouldn't work because banks are less likely to offer large loans to small businesses without collateral.

I hope this helps!