The group number of the element with atomic number $96$ is $3$.

There are 18 groups in the current periodic table, which is vertically organised in columns. Each group has a range of atoms with a certain atomic number.

Due to it, Nuclear Number: 3
Number of the element's group with atomic number 96=3.
It is accurate to say that an element with the atomic number 96 belongs to the third group, and here's why:
1. Curium is a member of the actinide class and has the atomic number 96.
2. The elements in the actinide family have an atomic number between 89 and 103.
3. Since curium has an atomic number of 96, it is unquestionably a member of the actinide series.
4.The group 3 of the periodic table is where the actinide series is found.

The New Element Curium (Atomic Number 96).

Curium, with the chemical symbol Cm and atomic number 96, is a transuranic, radioactive chemical element. The famous scientists Marie and Pierre Curie, both of whom were recognised for their studies on radioactivity, inspired the naming of this actinide element.

Hence option (A) is correct.