TOEFL Reading: ETS-TOEFL阅读机经 - Y4A1V8YE515QRPMML$

What can be inferred from paragraph 2 about clay as a writing material? A. It had to be baked before it could be written on. B. Its good points outweighed its bad points. C. Its durability was its most important feature for its users. D. It was not available in Egypt.