During a Sprint grooming, as a facilitator (optional) of the meeting, SM can ensure that event takes place, is time bound, conversation is focussed on the topic, makes sure Acceptance Criteria, Estimations are provided.
What other specific questions can a SM ask during grooming without sounding like a Manager or exceeding the authority?
For example, can SM ask any of the following questions?
The key output of backlog refinement is that you are ready for sprint planning.
As a Scrum Master a question I ask a lot at backlog refinement is:
Are you happy that we can take this story in to sprint planning?
If the team likes to do estimation during backlog refinement then I would also often ask:
Do you have enough information to estimate on this story?
The questions you mention would be acceptable in a lot of teams, but I would prefer to rephrase them to be prompts to the team rather than being so specific.
For example, rather than:
How will you test it?
I would prefer to ask:
Are you happy we have considered the testing aspects of this story?
To add to the existing suggestions, I also like to ask what other dependencies might exist, e.g. the deployment of another task in the same sprint or environment.
This may help the team think outside the box and detect possible dependencies/limitations, which should be added in a comment on the ticket.
I try to make sure that everybody can share their opinion. Some people are more reserved and do not answer a general questions because some else did that (even though they do share the opinion of the other person).
I also try to read body language; try to see if everybody is in agreement with what has been said
