You want to send and consume Cloud Pub/Sub messages from your App Engine application. The Cloud Pub/Sub API is currently disabled. You will use a service account to authenticate your application to the API. You want to make sure your application can use Cloud Pub/Sub.
What should you do?
A . Enable the Cloud Pub/Sub API in the API Library on the GCP Console.
B . Rely on the automatic enablement of the Cloud Pub/Sub API when the Service Account accesses it.
C . Use Deployment Manager to deploy your application. Rely on the automatic enablement of all APIs used by the application being deployed.
D . Grant the App Engine Default service account the role of Cloud Pub/Sub Admin. Have your application enable the API on the first connection to Cloud Pub/Sub.
Answer: A