Given below are two statements : Statement (I) : The 4f and 5f - series of elements are placed separately in the Periodic table to preserve the principle of classification. Statement (II) : s-block elements can be found in pure form in nature. In light of the above statements, choose the most appropriate answer from the options given below:

Step-by-step solution

The Lanthanides 4 f - and Actinides 5 f - inner transition series of elements are placed separately at the bottom of the periodic table. Reason: (i) This prevents the undue expansion of the periodic table i.e., maintains its structure and (ii) also because their properties are different from other elements. The main reason that s-block elements never occur in free state/nature is that these are alkali and alkali earth metals which are highly reactive. The high reactivity comes from their low ionization energy. They