Why do lags make if difficult to fine tune the economy?

Leticia has worked for 20 years in the public relations department of a large firm and has been the vice-president for the past ten years. it is unlikely she will ever be promoted to the top executive position in her firm even though she has directed several successful projects and is quite capable. her lack of promotion is an illustration of (a) the "glass ceiling" (b) the "glass elevator" (c) the "mommy track" (d) sexual harassment