The chairman of a big company visits one department on Monday of every week except for the Monday of third week of every month.     I. He visited Accounts department in the second week of September after having visited Purchase department on the earlier occasion.      II. He had visited Purchase department immediately after visiting stores department but before visiting Accounts department.    When did he visit the Purchase department?.

• A. 100
• B. 150
• C. 200
• D. 160