Final answer:
Messaging each other during an open book exam to find answers is considered cheating.
Step-by-step explanation:
The correct answer is c) Cheating. Messaging each other during an exam to find answers in the book is considered cheating. Although the exam is open book, it does not mean that students can collaborate or message each other for answers. They are expected to complete the exam independently, using the book as a resource to find information.