Answer:
Option B , I. and III.
Step-by-step explanation:
From statement I and III, it is clear that four children out of seven children suffer from blue skin complexion which is not something very common to occur in a family without any hereditary background. Also the doctors claimed that blue skin issue is rarely seen these days. Thus, there are high chances of acquiring this problem from ancestors (affected or non-affected (carriers))
Therefore, both options I and III depict that some where the origin of blue skin disorder is associated with hereditary of the family.
Hence, option B is correct