Correct Option (C)
Assumption 1 is valid. The passage states that "changes in the climate and the atmosphere's chemistry will affect the prevalence and virulence agricultural diseases" and that "such changes will make some plant infections more common in all climatic zones." This implies that climate change can facilitate the spread or migration of plant diseases into new geographical regions where they were previously not prevalent.
Assumption 2 is also valid. The passage explains that "centuries of selective breeding have refined the genomes of most high-value crops," resulting in "genetic variations that are not immediately useful to them have been bred out." This makes these crops vulnerable to "changes" and new diseases. The inference is that genetic diversity, often preserved in the wild relatives of crops, is crucial for resilience against evolving threats. Therefore, a scientific understanding of these wild relatives would enable the reintroduction of beneficial genetic traits, thereby enhancing the adaptability and disease resistance of crops and strengthening food security.
Incorrect Options:
Options (A) and (B) are incorrect because they propose that only one of the assumptions is valid, whereas the passage provides clear support for both Assumption 1 and Assumption 2. Option (D) is incorrect as both assumptions are directly inferable from the text provided in the passage.