|A) If the data in statement I alone are sufficient to answer the question
|B) If the data in statement II alone are sufficient answer the question
|C) If the data either in I or II alone are sufficient to answer the question;
|D) If the data in both the statements together are needed.
From II. we can conclude that 500 boxes were sold on Sunday
From I. we find that number of boxes sold on Monday 500 +10% of 500 = 550.