Which of these statements about fragmentation is FALSE?

Question $7$Select one:

a$.$

In vertical fragmentation, fragments have different schemas.

b$.$

In horizontal fragmentation, no tuples $($rows$)$ can appear in more than one fragment.

c$.$

In vertical fragmentation, primary key attributes must appear in every fragment.

d$.$

In horizontal fragmentation, fragments have different schemas.

e$.$

Each data item in the global relation must appear in at least one fragment.

f$.$

In horizontal fragmentation, primary key attributes appear in every fragment.