Answer:
C. Dana does not want Ms. Foster to know she has been crying.
Step-by-step explanation:
The fact that when Dana heard Ms. Foster coming and wiped her eyes suggests that she was trying to hide that she had been crying. Additionally, when Ms. Foster asked if Dana was okay, Dana lied and said that she was fine. That also proves she was trying to hide something. Finally, Dana changed the subject to her grades to avoid any other questions regarding her crying and to redirect Ms. Foster's attention to what Dana had, most likely, been called in for.
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