Почему QualitySettings ругается на names? И на GetQualityLevel?

Почему QualitySettings ругается на names? И на GetQualityLevel?

Assets/Scripts/GraphicSettings.cs(16,45): error CS0117: QualitySettings' does not contain a definition fornames'

Assets/Scripts/GraphicSettings.cs(17,42): error CS0117: QualitySettings' does not contain a definition forGetQualityLevel'

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using System.Linq;

public class GraphicSettings : MonoBehaviour {
    public Dropdown dropDown;
    void Start () {
        dropDown.ClearOptions();
        dropDown.AddOptions(QualitySettings.names.ToList());
        dropDown.value = QualitySettings.GetQualityLevel();
    }
    void Update () {
    }
}