The rest of the scenarios happened to me so I have my own feelings mixed into it. Scenario 4 (what I said to the lab tech), would be the second most direct, then scenario 1, finally scenario 2. All of those examples, IMO are examples of direct communication because I understood what they were getting at, which was basically get to work and in my case I wanted her to change her gloves and she understood that."Sit down and read this article I've written. Think about it carefully. Then I want to talk to you about when and how to use direct and indirect communication at work."
Indirect communication to me would be an exchange that happens frequently between my boss and I.
Me: Are there any particular projects you'd like to have an update on at our meeting?
Boss: No, just bring what you think is important.
What I think is important and what she thinks is important are could very well be two different things. Our meetings often end up that I bring absolutely everything I'm working on and spending time on things that are not priorities or could be handled through email.
Then there's the aspect of interpersonal direct and indirect communication which is so complex that it's hard to even tackle without a bunch of background info and detail. I'm just trying to keep it simple so people can begin to think about their communication patterns.