Katrina, an experienced and resourceful employee, was not promoted as a manager in spite of being well deserving. Her male counterparts, who are not as efficient as her, have been promoted and given a pay raise. It appears that Katrina's only disadvantage is that she is a woman. This discrimination against Katrina is explained by the concept of _____.

A glass escalator is a concept used in business to say when men get promotions and a pay raise faster than women, just because they are men, while women find it harder to get a promotion, if they can get one at all. It is used specially for women dominated jobs, or jobs who are typically done by women, in which women strive to get a promotion or a pay rise, but they are stuck in their place, as Katrina, hitting what in business is called a "glass ceiling", that is to say, a limit (a "ceiling") which is unofficial or cannot be seen (that's why it is a "glass") but it is there as reality shows she can't move forward.

The term "glass escalator" makes reference that you have women striving to rise but hitting this "glass ceiling", like going up the stairs all full of people and not getting nowhere, but right next to them, there's an invisible escalator in which men can go up faster.

So the concept is used for both, for saying men have it easier to get a promotion and for saying women have it harder to get it, compared with men, as Katrina. The question is actually an example of what the glass escalator means.