Read the passage from When Birds Get Flu and Cows Go Mad! by John DiConsiglio. Japan, for example, tests a sample from every cow that will be used for food. The meat is kept in refrigerators until the test comes back negative. Most European nations test about 70 percent of their cows.

But in the U. S., only about 650,000 of the 35 million cattle slaughtered each year are tested.

The author sets the tone with his use of {blank}

Options:
1. Word Order
2. Statistics
3. Signal Words
4. Punctuation