This goes too far beyond the author's point. The author doesn't argue that the Mayans should win their lawsuit. She merely argues that Belize courts should recognize indigenous rights. This might suggest that the lawsuit should go forward, but that doesn't imply the author thinks the logging concessions are definitely a violation of indigenous rights.

The author never indicates that Belize's common-law system already permits lawsuits asserting indigenous rights. The author argues that the system should recognize indigenous rights, because common law and international law support such recognition. But that doesn't mean Belize's system currently permits these lawsuits.

The author never indicates that Belize has failed to recognize indigenous rights after hearing the lawsuit brought by Mayans. Courts in Belize haven't ruled yet on indigenous rights, but that doesn't mean that they decided not to recognize such rights upon hearing the lawsuit.

The main point of the passage isn't to state what would be true if Belize courts don't recognize indigenous rights. The author argues that precedent supports recognition of indigenous rights. That's a view about how Belize courts should recognize such rights and about the viability of the Mayans' lawsuit. But it's not a view about how a bad decision in the Mayan case might set unsound precedent. In addition, it's not clear that the author believes failure to recognize indigenous rights would be unsound. Although the author believes there should be a presumption in favor of those rights, this isn't the same as saying those rights should definitely be found to exist.

This captures the main point the best out of the five available answers. The author argues that courts in Belize should adopt the presumption that recognizes the existence of indigenous rights. The author makes this argument in connection with a discussion of the Mayans' lawsuit, implying that there is at least some merit to the Mayans' position.