async getOption(optionIndex) {
        const activeOptions = await $(this.rootElement).$$('li[data-selected="false"]');
        const option = activeOptions[optionIndex];
        if (option && !option.error) {
            return new PageOption(option, await this[privateGetMenuBoundsRect]());
        }
        return null;
    }
Returns a new Option page object of the element in item position.
@method
@param {number} optionIndex - The base 0 index of the Option.