Which code fragments, inserted independently, enable the code compile?

Given the code fragment Which code fragments, inserted independently, enable the code
compile?

A.
this.fvar = 200; this.cvar = 400;

B.
t.fvar = 200; Test2.cvar = 400;

C.
cvar = 400;

D.
t.fvar = 200;

E.
fvar = 200; cvar = 400;

F.
this.fvar = 200; Test2.cvar = 400;

Explanation: