I will modify the "Participating Users" selection component in `src/pages/admin/ExamTaskPage.tsx` to support displaying up to 50 users with a scrollbar and automatic sorting.

**Implementation Steps:**

1. **Add Custom CSS (`src/index.css`):**

   * Add a `.user-select-scrollable` class to handle the scrollbar logic for the Ant Design Select component.

   * Set `max-height` (e.g., 120px) and `overflow-y: auto` for the `.ant-select-selector` to ensure it scrolls when many users are selected.

2. **Update Component (`src/pages/admin/ExamTaskPage.tsx`):**

   * **Remove Restrictions:** Remove `maxTagCount={3}` and `maxTagPlaceholder` props from the `Select` component to allow all selected users to be displayed.

   * **Apply Style:** Add `className="user-select-scrollable"` to the `Select` component.

   * **Implement Sorting:** Add a `normalize` function to the parent `Form.Item`. This function will intercept value changes and sort the selected User IDs alphabetically by their names (using `localeCompare` for Chinese support).

3. **Verification:**

   * Ensure the development server is running.

   * Provide a preview URL for you to test the changes (User selection should expand, show a scrollbar after filling up, and selected names should automatically sort).

