Clarification of the Product Owner responsibility

Hi,
I have a technical question about something I found in the Scrum Guide:

"The Product Owner is responsible for maximizing the value of the product and the work of the Development Team."

I don't want to be picky, but this could mean two things:

The Product Owner is responsible for maximizing the value of the product.
The Product Owner is responsible for the work of the Development Team.

Or:

The Product Owner is responsible for maximizing the value of the product.
The Product Owner is responsible for maximizing the work of the Development Team.

So is the PO responsible for THE WORK of the development team (responsible for the performed work) or for MAXIMIZING the work of the development team (responsible to ensure they're as productive as possible in their work?)

I assume it's the first one, it makes more sense. But since I'm preparing for the assessment, I don't want to miss a question by not understanding this right. Thank you for any input you might have.

Alan