SAT English Practice Question

A team of researchers studied the impact of a new type of fertilizer on crop yield. The researchers grew two groups of corn plants, one group that received the new fertilizer and one group that did not. The researchers found that the corn plants that received the new fertilizer grew significantly taller than those that did not. The researchers concluded that the new fertilizer increased crop yield.

1. A.taller than those that did not; the researchers
2. B.taller than those that did not, the researchers
3. C.taller than those that did not. The researchers
4. D.taller than those that did not; the researchers