# $O^{2-}$ and $Si^{4+}$ are isoelectronic ions. If the ionic radius of $O^{2-}$ is $1.4 \mathring{A}$, the ionic radius of $Si^{4+}$ will be :
( A ) $2.8 \mathring{A}$
( B ) $0.41 \mathring{A}$
( C ) $1.5 \mathring{A}$
( D ) $1.4 \mathring{A}$