Could someone tell which answer is the right one according to text

[Aaaaa11111]

...
Japan calls it an island and claims it as territory, which it says gives
it the right to an exclusive economic zone (EEZ) of 400,000 square
km – larger than Japan’s land mass itself. The surrounding sea is rich
in tuna, but is also militarily important to China. If rising sea levels
swamp the land (which is already encased in concrete), Japan loses
its claim to the EEZ.
So far, star sand has only been grown in the laboratory. It may not
even make it to Okinotorishima if lawyers decide that land propped
up by artificial star sand does not count as an island – in which case
it would not merit an EEZ
...

the question is:

12. Why may Japan’s plans fail?
A The use of star sand could be found illegal
B Star sand is possibly too artificial
C The EEZ might forbid the use of star sand

What do you guys think?

[Mister Micawber]

Hello, Aa, and welcome to English-test. net.

First, I would like to see your answer. Read the passage carefully and see which answer is accurate. Then we will check your effort.
_________________
Native English teacher at Mister Micawber's

[Aaaaa11111]

Well, I'd say C but the right answer is A. I just can't understand why.

[Mister Micawber]

Here is the key phrase in the text, Aa:

'if lawyers decide that land propped up by artificial star sand does not count as an island'.

Now, what do you think?
_________________
Native English teacher at Mister Micawber's

[Aaaaa11111]

Still, I don't get it why it would be ILLEGAL