Explanation

The S-block includes Group 1 (alkali metals) and Group 2 (alkaline earth metals) along with helium, totaling 14 elements.

These elements have their outermost electrons in the s-orbital.

Additional Information:

P-block → 6 groups (13–18) → 38 elements

D-block → Transition metals (Groups 3–12) → 40 elements

F-block → Lanthanides + Actinides → 28 elements