I find the term "the team" a bit confusing. I know what we're going for here, but it is a vague term, so I would expect some confusion on the answers.

The "Team" is the right answer, because the Team consists of all members of the Scrum Team that are actually working to produce PBIs. The Scrum Master and Product Owner may be members of the Team, if they are working on PBIs as well as doing their PO and SM stuff.
I think the problem here is in the Guide, not the question. In the Guide (pg 3), the Team is defined by "The Team consists of developers with all the skills to turn the Product Owner’s requirements into a potentially releasable piece of the product by the end of the Sprint." I think this needs to be extended with something like "The SM and PO may be members of the Team if they are actively working on product" or something like that. This is said later in the Guide, when talking about the PO and SM, but it needs to be more clear when the "Team" itself is defined, IMHO.
I have two other comments about the Daily Scrum and the Guide:
1. The Guide says "Each Team meets daily for a 15-minute status meeting called the Daily Scrum." and it also says "The Daily Scrum is not a status meeting" four paragraphs later. The word "status" needs to be removed from the first sentence.
2. I am confused by the word "pig." On pg 4 of the guide the definition of "pig" is all members of the Scrum Team: the PO, SM, and Team Members. On pg 7 it says that "The Product Owner and ScrumMaster roles are not included in this count unless they are also pigs," which indicates to me that the only pigs are Team Members. In the discussion of the Daily Scrum, pg 13, it says "...chickens are not allowed to talk..."
I propose that the word "pig" in the second case be changed to "Team Members," and that the last sentence be changed to "...non-Team members are not allowed to talk..." If you do that it makes things clear, and the whole "chicken and pig" story can be removed from the Scrum Guide as being superfluous.

Thanks, Dan ;-)

I agree with 'a' being the right answer, but also with the given remarks.
The term "Team" is confusing because of its dual use. Maybe the suggestion of the ScrumAlliance's Scrum Guide to use "Development Team" over "Team" can help? (by the way, Ken, did you (co)write that Scrum Guide as well?) The Scrum Team would then consist of Development Team, Product Owner and ScrumMaster. All are pigs!
With regards to the question itself: I understand it as "Who is AT LEAST required to attend the Daily Scrum?" (without asking to rephrase it). In my teams all pigs participate in the Daily Scrum, because of the broader information sharing (not: status). Committed people love to be informed on all aspects of the project/product development!
Note: at various fora I was surprised by lots of Scrum Developers (a) wanting to forbid PO or SM to attend the Daily Scrum and (b) calling PO's chickens. Both views are against the essence of Scrum, IMHO.