Dropdowns with Select

<select id="sort">
  <option value="relevance" selected>Relevance</option>
  <option value="price-asc">Price: Low to High</option>
  <option value="price-desc">Price: High to Low</option>
  <option value="newest">Newest First</option>
</select>

import org.openqa.selenium.support.ui.Select;

Select sort = new Select(driver.findElement(By.id("sort")));
sort.selectByVisibleText("Price: Low to High");   // what the user sees
sort.selectByValue("newest");                     // value attribute
sort.selectByIndex(2);                            // 0-based position

System.out.println("Selected: " + sort.getFirstSelectedOption().getText());
for (WebElement option : sort.getOptions()) System.out.println(" - " + option.getText());
System.out.println("Multiple? " + sort.isMultiple());

Run SortDropdownTest.main()

Selected: Price: High to Low
 - Relevance
 - Price: Low to High
 - Price: High to Low
 - Newest First
Multiple? false

Many modern sites build dropdowns from <div> and <li>, not <select>. Select then throws UnexpectedTagNameException: Element should have been "select" but was "div". Click to open, then click the option:

driver.findElement(By.cssSelector(".city-picker")).click();
wait.until(ExpectedConditions.elementToBeClickable(By.xpath("//li[normalize-space()='Bengaluru']"))).click();