What is a key architectural limitation of using multiple Pub/Sub push subscriptions for the same topic?

Question

Google Cloud (GCP) — Hard

What is a key architectural limitation of using multiple Pub/Sub push subscriptions for the same topic?

Accepted Answer

When using multiple Pub/Sub push subscriptions for the same topic, each subscription receives all messages independently. This leads to duplicated message delivery and processing overhead. The correct answer highlights this key limitation. Incorrect options, such as A and C, introduce unrelated constraints.