Among the following elements, the one that is not an actinoid is:

1. Curium (Z=96) 2. Californium (Z=98)
3. Uranium (Z=92) 4. Terbium (Z=65)

HINT: Actinoids atomic number start from 89.

Explanation:

Elements with atomic number, Z=89 to 103 are called actinoids. Thus, Terbium (Z=65) is not an actinoid.

Terbium belong to lanthanoids.