Final answer:
The provided information from Caroline Krafft and UNESCO's GRALE report does not directly answer the question about the percentage of adults with a specific level of health literacy, but discusses general literacy improvements and challenges for disadvantaged groups.
Step-by-step explanation:
The question pertains to the percentage of adults who possess a certain level of health literacy. The data provided, however, does not explicitly mention the exact figure for health literacy among adults. Health literacy involves the ability to understand and make informed decisions based on health information, which can be influenced by general literacy rates.
According to Caroline Krafft's information, general literacy and education have seen significant improvements over time, with adult literacy being a more specific issue mentioned by UNESCO's GRALE report, revealing challenges in literacy for disadvantaged groups. Although the information provided includes literacy statistics and discussions, it does not contain a direct answer to the given question about the percentage of adults with a specific level of health literacy. Therefore, a relevant and accurate response cannot be deduced from the provided reference material.