Which of the following enhancements can be estimated using FP methodology?

Select one:

a$.$ Changes to the operating system from version $3\mathrm{.}0$ to version $4\mathrm{.}0$

b$.15$ changes to the batch jobs that maintain $15$ different logical data groups

c$.$ Changes to the hardcppled tables in the system that source $15$ different code data values

d$.$ Change of the Webserver from version $2\mathrm{.}0$ to the higher version $3\mathrm{.}0$