$\begin{array}{1 1} \text{(a) Hydrogen’s nucleus is electron deficient when it bonds with an electronegative atom.} \\ \text{(b) Hydrogen is the only atom that is the same size as an oxygen atom.} \\ \text{(c) Hydrogen is the most electronegative element.} \\ \text{(d) Hydrogen tends to form covalent bonds.}
\end{array} $
