Salesforce Slack-Dev-201 Based on Real Exam Environment

Slack modals are opened through the `views.open` Web API method using Bolt's built-in API client. After a shortcut, slash command, button click, or another qualifying interaction, Slack supplies a `trigger_id`. The application acknowledges the incoming interaction and promptly exchanges that trigger through `views.open` together with a valid modal view payload. In Bolt for JavaScript, this is commonly represented through the client's `views.open` interface; Bolt for Python exposes the corresponding `client.views_open()` method. The important platform primitive is therefore `views.open`, regardless of the language-specific SDK naming convention. A `trigger_id` must be used quickly because it has a short validity period. Neither `app.modal()` nor `app.popup()` nor `client.modal.show()` is Slack's documented method for opening modal views. Therefore, B is the correct answer.

Socket Mode allows a Slack application to receive Events API and interactive payloads through a WebSocket connection rather than exposing a publicly accessible HTTP Request URL. The application establishes an outbound connection to Slack, making Socket Mode particularly useful during local development, behind corporate firewalls, or in environments where inbound public HTTP traffic cannot be accepted. Slack dynamically creates the WebSocket URL through `apps.connections.open`; the URL is not a permanent endpoint. Socket Mode does not remove OAuth requirements, eliminate Block Kit, or eliminate application installation. Bot and user functionality still depends on the application's authorization model and appropriate scopes. Socket Mode simply changes how Slack delivers events and interactive payloads to the application. Therefore, B precisely identifies the architectural advantage tested by the question.

Slack applies OAuth authorization at the API-method level. If an access token does not contain the scope required by the requested Web API operation, Slack rejects the call rather than silently granting additional privileges or returning unauthorized data. A common response is the `missing_scope` error, which indicates that the token lacks the specific scope permissions necessary to complete the operation. Slack's permissions model therefore enforces least privilege: an application's token can perform only the actions authorized through its granted scopes. Adding a scope to app configuration does not automatically upgrade an already issued token; existing installations may need reauthorization when new required scopes are introduced. Slack also does not normally email an administrator merely because an API request lacks a scope. Therefore, B accurately represents Slack's authorization behavior.

In Bolt for Python, `@app.message(...)` registers a listener for messages matching specified text or a regular-expression pattern. For example, `@app.message("hello")` can invoke a listener when an incoming message contains the expected text. Bolt handles the event routing and supplies useful listener arguments such as the message payload, `say`, `client`, and other context values. By contrast, `@app.event` is used to subscribe a listener to a specific Slack event type rather than to filter messages by text. `@app.listen` and `@app.on_message` are not the standard Bolt for Python decorators documented for this use case. Therefore, B is correct: `@app.message` is the framework feature specifically intended for listening to message content that matches a configured string or pattern.