The Wall Street Journal about the effect of automation on jobs

In an article in the Wall Street Journal about the effect of automation on jobs, Boston University economist James Bessen is quoted as saying that the problem is not “mass unemployment, it’s transitioning people from one job to another.” Source: Christopher Mims, “Automation Can Actually Create More Jobs,” Wall Streetfournal, December 11, 2016. What does “transitioning people from one job to another” entail and what type(s) of unemployment would describe these people? A. In this case, it would involve helping those who are cyclically unemployed find jobs during a recession.
B. In this case, it would involve helping those who are structurally unemployed acquire the skills needed to find new jobs. C. In this case, it would involve helping those who are underemployed move from part-time to full-time jobs. D. In this case, it would involve helping those who are frictionally unemployed so they no longer feel discouraged.