When alleles in a chromosome pair are identical, they are said to be

Cyrus is studying the effects of meditation on coping with illness. In his sample of participants with serious illness, he has the treatment group do an hour-long meditation and the control group listen to the news for an hour. To eliminate the possibility that the meditation, rather than a difference in how comfortable the chairs used by the treatment and control group participants were, causes changes in the participants' coping, Cyrus should use: _______

A. random assignment B. random sampling C. experimental control D. a prospective design

Some women can tell when they are ovulating

a. True b. False