Three elements $A$, $B$, and $C$ have $3$, $4$, and $2$ electrons respectively in their outermost shell. Determine the group number to which they belong in the Modern Periodic Table and state their valencies.

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(N/A) The group number of an element in the Modern Periodic Table can be determined by its valence electrons. For elements with valence electrons greater than $2$, the group number is calculated as $(10 + \text{number of valence electrons})$.
$1$. For element $A$ (valence electrons = $3$): Group number = $10 + 3 = 13$. Valency = $3$.
$2$. For element $B$ (valence electrons = $4$): Group number = $10 + 4 = 14$. Valency = $4$.
$3$. For element $C$ (valence electrons = $2$): Group number = $2$. Valency = $2$.
ElementGroup NumberValency
$A$$13$$3$
$B$$14$$4$
$C$$2$$2$

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