[Grammar] A, B, and/or C

[Snappy]

"The Ministry must implement plan A, B, or C."
I think the above sentence means that the Ministry must implement plan A or plan B or plan C, and in other words, if the Ministry implements one of these plans, the Ministry does not have to implement the other plans.

"The Ministry must implement plan A, B, and/or C."
I think this sentence is a little awkward, but "and/or" often appears in formal documents. In my understanding, this sentence means that the Ministry must implement at least one of these plans, in other words, the Ministry may have to implement two or all of the plans in some cases.

Please confirm whether my understanding is correct.

 

[SlickVic9000]

(Not a Teacher)

I think you've got the right idea.
The first sentence suggests that the Ministry can only implement one of these plans.
The second sentence suggests that the Ministry could implement one, two, or all three of these plans in any combination.

 

[Raymott]

"The Ministry must implement plan A, B, and/or C."
I think this sentence is a little awkward, but "and/or" often appears in formal documents. In my understanding, this sentence means that the Ministry must implement at least one of these plans, in other words, the Ministry may have to implement two or all of the plans in some cases.

Please confirm whether my understanding is correct.

It's not a good sentence. It could easily be read as a choice: ((A + B) or C) or all three. That is, if A is used, B must be too.
Better: "The Ministry must implement plan A, B, or C or some combination thereof." This has the benefit being not only correct, but also of being intelligible.