IWebElement element = _browserInstance.Driver.FindElement(By.XPath("//Select"));
IList<IWebElement> AllDropDownList = element.FindElements(By.XPath("//option"));
int DpListCount = AllDropDownList.Count;
for (int i = 0; i < DpListCount; i++)
{
if (AllDropDownList[i].Text == "nnnnnnnnnnn")
{
AllDropDownList[i].Click();
_browserInstance.ScreenCapture("nnnnnnnnnnnnnnnnnnnnnn");
}
}