Answer:
C. Anthony's headache vexed him all morning, so he decided to take a break from writing his research paper.
Explanation:
The correct answer is Option C.
This is true because looking at the meaning of vex, one will discover that it means to cause perplexity and to bring distress or suffering
This means that Anthony's headache caused him distress which made him to have a break from writing his research paper.
