Consider the following operations performed on a list L that is initially empty $($i$.$e$.$ it has no list elements, like an empty playlist.$)$

L$.$add$(0,$ d$)$

L$.$add$(0,$ b$)$

L$.$add$(1,$ c$)$

L$.$add$(0,$ a$)$

This has produced a modified list L$.$

Match each of the following operations on this modified list L to their output. $($That is$,$ consider each of the following operations as the fifth operation after the four above; they are themselves not cumulative.$)$

L$.$remove$(3)$

L$.$set$(2,$x$)$

L$.$size$()$

L$.$add$(0,$x$)$