Removing InternationalShippingServiceOptions using the .NET SDK

public string ReviseItem(string itemID)
{
   ReviseItemCall call = new ReviseItemCall(GetContext());
   ItemType item = new ItemType();
   item.ItemID = itemID;
   item.ShippingDetails = new ShippingDetailsType();

   //Mention all the domestic Shipping Service Options
   item.ShippingDetails.ShippingServiceOptions = new ShippingServiceOptionsTypeCollection();
   ShippingServiceOptionsType[] opt = new ShippingServiceOptionsType[2];
   opt[0] = new ShippingServiceOptionsType();
   opt[0].ShippingServiceCost = new AmountType();
   opt[0].ShippingServiceCost.currencyID = CurrencyCodeType.USD;
   opt[0].ShippingServiceCost.Value = 4.25;
   opt[0].ShippingServiceAdditionalCost = new AmountType();
   opt[0].ShippingServiceAdditionalCost.currencyID = CurrencyCodeType.USD;
   opt[0].ShippingServiceAdditionalCost.Value = 1.5;
   opt[0].ShippingService = "ShippingMethodStandard";
   opt[0].ShippingServicePriority = 1;
   item.ShippingDetails.ShippingServiceOptions.Add(opt[0]);

   opt[1] = new ShippingServiceOptionsType();
   opt[1].ShippingServiceCost = new AmountType();
   opt[1].ShippingServiceCost.currencyID = CurrencyCodeType.USD;
   opt[1].ShippingServiceCost.Value = 7.0;
   opt[1].ShippingServiceAdditionalCost = new AmountType();
   opt[1].ShippingServiceAdditionalCost.currencyID = CurrencyCodeType.USD;
   opt[1].ShippingServiceAdditionalCost.Value = 3;
   opt[1].ShippingService = "USPSPriority";
   opt[1].ShippingServicePriority = 2;
   item.ShippingDetails.ShippingServiceOptions.Add(opt[1]);
   
   //Specify an empty InternationShippingServiceOption object
   item.ShippingDetails.InternationalShippingServiceOption = new InternationalShippingServiceOptionsTypeCollection();
   InternationalShippingServiceOptionsType Iopt = new InternationalShippingServiceOptionsType();
   Iopt = new InternationalShippingServiceOptionsType();
   item.ShippingDetails.InternationalShippingServiceOption.Add(Iopt);

   FeeTypeCollection fees = call.ReviseItem(item, null);
}

  // Set Auth&Auth Token for the call
 
  context.ApiCredential.eBayToken = "token";

  // Set the URL
  context.SoapApiServerUrl = "https://api.sandbox.ebay.com/wsapi"; 

  // Set logging
  context.ApiLogManager = newApiLogManager();
  context.ApiLogManager.ApiLoggerList.Add(new eBay.Service.Util.FileLogger("Messages.log", true, true, true));
  context.ApiLogManager.EnableLogging = true;

  // Set the version
  context.Version = "1131";

  return context;