一对表现正常的夫妇，他们的基因型是Bb。预计他们生育一个白化病的孩子基因是[ ]
A．BB
B．Bb
C．BB或Bb
D．bb
答案：D
应用白喉抗毒素的注意事项有哪些?
What does the speaker say about the artists in the United States during the Great Depression
A．Many artists lost faith in the value of art.
B．Many artists were forced to take jobs in other fields.
C．Many artists moved away from large cities.
D．Many artists in the United States moved to other countries.
