@When("I enter $elementId value $value")
public void enterElementText(final String elementId, final String value) {
    final WebElement webElement = webdriver.findElement(By.id(elementId));
    webElement.clear();
    webElement.sendKeys(value);
}

@When("I select $elementId value $value")
public void selectComboValue(final String elementId, final String value) {
    final Select selectBox = new Select(web.findElement(By.id(elementId)));
    selectBox.selectByValue(value);
}

Actions builder = new Actions( driver );
Action  action  = builder.click( driver.findElement( By.id( elementId ) ) ).build();
action.perform();

using OpenQA.Selenium.Support.UI;

SelectElement select = new SelectElement(driver.findElement( By.id( elementId ) ));
select.SelectByText("Option3");
select.Submit();