Which of the following is/are electron deficient compounds?

Each Boron binds with 4 hydrogen atoms to form the Diborane structure. Boron's valency, however, is 3. Each of the four boron atoms contributes three valence electrons, but the fourth bond is electron deficient since there isn't a valence electron from the boron atom to offer. 

Three Al atoms are joined to three $\mathrm{Cl}$ atoms in ${\mathrm{AlCl}}_3$. But this instance breaks the octet rule. Eight electrons are present since there are no bonds or lone pairs. Only 3 bonds, or 6 electrons, are present. In other words, it lacks electrons.