Approximately how many chemicals are listed in CAS according to the material?

Approximately how many chemicals are listed in CAS according to the material?

• A. over 50 thousand
• B. over 1 million
• C. over 1 billion
• D. over 113 million

Answer: (D)

The main idea is how large the CAS registry is. The material states that more than 113 million chemical substances are listed in CAS. That shows the vast breadth of the database, far exceeding tens of thousands or single-digit millions, and it isn’t described as exceeding a billion in the material. Knowing this helps you understand why CAS numbers are so valuable for precisely identifying chemicals in hazmat situations, since the registry links each substance to its data, hazards, and handling information. The other options don’t fit because they either greatly understate the registry’s size or claim an amount the material doesn’t specify.

The main idea is how large the CAS registry is. The material states that more than 113 million chemical substances are listed in CAS. That shows the vast breadth of the database, far exceeding tens of thousands or single-digit millions, and it isn’t described as exceeding a billion in the material. Knowing this helps you understand why CAS numbers are so valuable for precisely identifying chemicals in hazmat situations, since the registry links each substance to its data, hazards, and handling information. The other options don’t fit because they either greatly understate the registry’s size or claim an amount the material doesn’t specify.