A:气态氢化物的稳定性:HX>H2Y>ZH3
B:非金属活泼性:Y<X<Z
C:原子半径:X>Y>Z
D:原子最外电子层上电子数的关系:Y=X+Z
— Who came to school earliest yesterday morning?
— ______. You can ask Linda. She may know.