How to select an item from the drop-down list, with the selected class name

How to select a value from Drop-Down in DHTML Grid Using Selenium WebDriver?

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By Double click in UMO Column, a drop-down will be seen.

I need to pick a item from that drop-down. But locator is unable to find the Drop-Down.

I am able to double click the field, not able to proceed after that(i.e., Control is not able to locate the drop-down).

Through Firebug, it is shown "Select Class"..

Is there any work around in selenium webdriver to select the item from that drop-down...?

Will be very helpful if u share idea regarding this.

new SelectElement(driver.FindElement(By.ClassName("<className>"))).SelectByIndex("");

new SelectElement(driver.FindElement(By.ClassName("<className>"))).SelectByText("");

 new SelectElement(driver.FindElement(By.ClassName("<className>"))).SelectByValue("");