Your best option is to find the element containing the text -
webdriver refers to the selenium driver object that you use to find your elements.
The code could be something like this (accuracy is not guaranteed since I'm coding on the fly):
// Find all the span elements
List<IWebElement> spans = webdriver.FindElements(By.Tag("span"));
// use Linq to query the list for the span you want
IWebElement span = spans.Where(x => x.Text.Contains("Active"));
// And now assert that span is not null - that is, we found an element with text = "Active"
Assert.IsTrue(span != null);
There are other ways to do this, including finding by class, finding a unique parent and using XPath to navigate the DOM to your target element, and so on.
I suggest you experiment a bit and possibly look up the WebDriver API for more information.