Consider the following Python Codescript in Lab $7$ for the Set Covering Problem:

$U=\{1,2,3,4,5\}$

$f=\{1,1,1,1,1\}$

Assume we want to cover element $2$ by at least $2$ different subsets and element $4$ by at least $3$ different subsets.

Which update should be done in the code?

a$.f=\{1,1,1,1,1,1,1,1\}$;

b$.f=\{1,2,1,3,1\}$;

c$.U=\{1,2,2,3,4,4,4,5\}$;

d$.U=\{1,2,2,2,3,4,4,5\}$;