using WebApplication2.MyWebServiceReference;

MyWebServiceReference.UserCredentials credentials = new UserCredentials();
credentials.username = "uname";
credentials.password = "pwd";

MyWebServiceReference.Options options = new Options ();
options.includeImages = false;
options.maxWidth = 0;
options.maxHeight = 0;
options.maxThumbnailWidth = 0;
options.maxThumbnailHeight = 0;

MyWebServiceReference.Result response = new Result();

MyWebServiceReference.SoapClient client = new SoapClient();
response = client.MyMethod(credentials, options, 100);

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:ws="http://ws.design.xyz.com">
  <soapenv:Header>
  <ws:Options>
     <ws:includeImages>1</ws:includeImages>
     <ws:maxWidth>1</ws:maxWidth>
     <ws:maxHeight>1</ws:maxHeight>
     <ws:maxThumbnailWidth>1</ws:maxThumbnailWidth>
     <ws:maxThumbnailHeight>1</ws:maxThumbnailHeight>
  </ws:Options>
  <ws:UserCredentials>
     <!--Optional:-->
     <ws:username>uname</ws:username>
     <!--Optional:-->
     <ws:password>pwd</ws:password>
  </ws:UserCredentials>
 </soapenv:Header>
 <soapenv:Body>
  <ws:MyMethod>
     <ws:Id>105304</ws:Id>
  </ws:MyMethod>
  </soapenv:Body>
 </soapenv:Envelope>