Hi srivatchu,
Your Web API method returning string value and you are trying to loop through the data using ng-repeat directive which is not possible.
If you want loop and write data then you need to return List or Array from Web API method and display using ng-repeat directive.
If you are returning string message then display the string message without using ng-repeat directive.
Check the below example.
Namespaces
using System.Web.Http;
API Controller 
public class EmployeeInformationController : ApiController
{
    [Route("api/EmployeeInformation/Get")]
    [HttpGet]
    public string Get()
    {
        string content = "Hello World";
        return content;
    }
    [Route("api/EmployeeInformation/GetArray")]
    [HttpGet]
    public string[] GetArray()
    {
        string content = "Hello World,Welcome";
        return content.Split(',');
    }
}
HTML
<!DOCTYPE html>
<html ng-app="MyApp">
<head>
    <meta name="viewport" content="width=device-width" />
    <title>Index</title>
    <script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/angularjs/1.3.9/angular.min.js"></script>
    <script type="text/javascript">
        var app = angular.module('MyApp', [])
        app.controller('MyController', function ($scope, $http) {
            $http.get('https://localhost:44323/api/EmployeeInformation/Get')
                .then(function (response) {
                    $scope.greeting = response.data;
                });
            $http.get('https://localhost:44323/api/EmployeeInformation/GetArray')
               .then(function (response) {
                   $scope.greetingArray = response.data;
               });
        });
    </script>
</head>
<body>
    <div ng-controller="MyController">
        <p>The content is {{greeting}}</p><hr />
        <p ng-repeat="m in greetingArray">The content is {{m}}</p>
    </div>
</body>
</html>
Screenshot
