Time left $1\mathrm{.}17\mathrm{.}33$

Chrismic Steel, a car parts manufacturer, pays employees a higher hourly rate as they learn to master more tasks on the production floor. Employees earn $$15$ per hour when hired and can earn up to $$28$ per hour if they have mastered all $12$ work units in the production process. Chrismic Steel is applying which of these reward systems?

a$.$ Skill$-$based pay

b$.$ Commission$-$based pay

C$.$ Piece$-$rate pay

d$.$ Job evaluation system

e$.$ Seniority$-$based pay