The parents of a 4-year-old with sickle cell anemia tell the nurse that they would like to have other children, but they’re concerned about passing sickle cell anemia on to them. Which health care team member would be the most appropriate person for the nurse to refer them to ？（）

A．Clergy.

B．Social worker.

C．Certified nurse midwife.

D．Genetic counselor.

流阶地主要是在气候变化和构造抬升共同作用下形成。通常情况下，气候变化控制着河流堆积下切，构造则为河流下切提供了驱动力和空间。下图、下表分别为渭河上游陇西段阶地的分布图和参数表。现代聚落主要分布在（）

 ；

A、T1

B、T3

C、T5

D、T7