Create a currency converter api in c#

Create an API that provide currency conversion functionality through some pre-configured sources like XE, Yahoo, Oanda. Each of these source expect FromCurrency, ToCurrency, Amount, Date parameters. Consider following points in the final solution.

a.) A request to the API will include the source and other parameters that are required by the source to process the request successfully.

b.) You can configure to disable any source at any time, without having to deploy the application again.