Explain why the rest of the group has metallic behavior but boron does not

Since boron only has two electron shells, it is about as capable of gaining electrons as it is of losing electrons, so it behaves as a metalloid

Explanation:

Since boron only has two electron shells, it is about as capable of gaining electrons as it is of losing electrons, so it behaves as a metalloid. The other elements in this group have more electron shells, so it is much easier for them to lose their valence electrons and they behave like metals

the answer is b, have negligible mass