From the list below, pick the one we can call "mass production".

Question $4$ options:

a$)$

continuous flow process and assemble$-$to$-$order strategy

b$)$

batch process and make$-$to$-$order strategy

c$)$

line process and make$-$to$-$stock strategy

d$)$

job process and make$-$to$-$order strategy