Why HBr has stronger attraction between molecules than CH3NH2?
EDIT (after title edited): $\ce{HBr}$ doesn't have stronger interaction than $\ce{CH2NH2}$, but it has dipole-dipole interaction as the strongest forces between it's molecules, which is obviously weaker than H-bonding.

Hydrogen bonding is the strongest intermolecular attraction. It is a type of dipole-dipole interaction1, but it is specific to Hydrogen.
In general, dipole-dipole interactions are considered weaker than H-bonding. The relative strength of forces are as follows,

Hydrogen bonding &gt;  Van der Waals dipole-dipole interactions &gt; Van der Waals dispersion forces

As per your question, (a), (c) and (d) have dispersion forces (as they're non-polar), while (b) has H-bonding as it's strongest interaction (not dipole-dipole).
Finally, as only (e) has dipole-dipole as it's strongest attraction between molecules, hence it's the answer.

Notes:
1: Dipoles are created due to difference in electronegativity. Below image shows that there is sufficient electronegativity difference to create a dipole. H-bonding and dipole-dipole interactions have same origins.


(Source: Master Organic Chemistry)