Question: A dietary supplement manufacturer developed a new calcium supplement that appears to increase the bone density in middle-aged women. When tested in a small clinical trial, the supplement was shown to cause a 15% increase in bone density in 8 out of 10 women. Before the supplement is offered to the general public, which step should the manufacturer take next?

  Options: 
 A. add a variety of vitamins to the supplement
 B. test the supplement on mice in the laboratory
 C. develop packaging that is attractive to women
 D. test the supplement on a larger sample of women
Answer: D