What characteristics do you expect from an electron-deficient hydride with respect to its structure and chemical reactions?

Options

1. AElectron-deficient hydrides have an excess of electrons and are highly stable.
2. BElectron-deficient hydrides have exactly the right number of electrons for stability.
3. CElectron-deficient hydrides lack sufficient electrons for stability and readily accept electrons from other at
4. DElectron-deficient hydrides have unpaired electrons in their electron configuration.