cannot implicitly convert type string to string[]

Question

public string[] GetAccessPointMacAddresses()
        {
            netshline = null;
            while ((netshline = sr.ReadLine()) != null)
            {
                int BSSIDNumber = 0;
                BSSIDNumber = Convert.ToInt32(netshline.IndexOf("BSSID" + 6));
                string result1 = netshline.Substring(netshline.IndexOf(":") + 1);
                return result1;
            }
        }

if i return result1 i am getting this error