Q.Which type of unemployment is caused by replacement of simple mobile phones into smart phones?

Unemployment caused by a change in technology — such as smartphones replacing simple phones — is frictional unemployment, option (d) (technological unemployment being a form of it).

Frictional unemployment arises from frictions or adjustments in the labour market, and one of its main causes is a change in technology. When new technology (smartphones) replaces older technology (simple mobile phones), workers skilled in the old method lose their jobs until they retrain or shift — this technological unemployment is classified a …