ASP.NET MVC System.Net.Mail with <strong></strong&g

我通过ASP发送电子邮件。. NET MVC System.Net.Mail和我的电子邮件正文有html标签在它的<strong></strong>，但当我发送电子邮件，文本看起来像这个<strong>MESSAGE</strong>而不是它是粗体，我怎么能解决这个问题?

下面是我的代码:

var message = "<strong>MESSAGE</strong>'n'n";
MailAddress to = new MailAddress(email2@example.com);
MailAddress from = new MailAddress("email@example.com");
MailMessage email = new MailMessage(from, to);
email.Subject = "Subject Line";
email.Body = message;
email.BodyEncoding = System.Text.Encoding.UTF8;
SmtpClient client = new SmtpClient("mail.example.com");

email.IsBodyHtml = true;