-----Shall I give you a ride as you live so far away？

------- Thank you． ____________．

A．Of course you can

B．If you like

C．It couldn’t be better

D．It’s up to you

21-三体综合征G/G易位型核型

A．47,XY,＋21
B．46,XY(XX)/47,XY(XX)，＋2l
C．46,XY(XX),-14,＋t(14q21q)
D．46,XY(XX),-21,＋t(21q21q)
E．46,XY,＋21