Binary fission occurs in

The correct option is C. Both (A) and (B).
Explanation
Amoeba and Paramecium are both unicellular organisms that reproduce asexually through a process known as binary fission.
In Amoeba, the division can occur in any plane, which is called simple or irregular binary fission.
In Paramecium, division occurs along the transverse axis (across its width), a process known as transverse binary fission.
Since binary fission occurs in both Amoeba and Paramecium, the option including both is correct.