Electron groups could be considered which of the following?
a. three or more unshared electrons
b. bonded pairs of electrons
c. any atom that's an ion
d. lone-pair electrons

Electron groups could be considered as  Lone pair electrons and bonded pairs of electrons.

Option D & B

Explanation:

The two or more electrons can be bonded by single bond, double bond, covalent bond of electrons can simply be lone pair of electrons. Unshared pair of electrons are generally termed as lone pair of electrons in an atom which are generally present in the outermost shell of atoms. Hence electron groups can be determined by bonded pairs and lone pairs of electrons.

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