[tex]{ \qquad\qquad\huge\underline{{\sf Answer}}} [/tex]
Alkali metals are the ones that belong to the 1st group of the periodic table, they are the most reactive metals having less ionization energy.
And one more thing is common between them, that is :
All alkali metals are soft metals, that can easily be cut through knife.
So, required choice is : B. Softer
