Assertion: The transition metals have low enthalpy of atomization.
Reason: Transition metals have strong inter atomic bonds.

Both assertion and reason are true and the reason is the correct explanation of the assertion. 

Both the assertion and the reason are true. Transition metals do have low enthalpy of atomization, meaning they require relatively less energy to break the metallic bonds and convert the solid metal into individual gaseous atoms. The reason provided is also correct because the low enthalpy of atomization in transition metals is indeed due to the presence of strong interatomic bonds, which are characteristic of metallic bonding in these elements. The strong metallic bonds arise from the delocalization of electrons in the d orbitals, which allows for efficient sharing of electrons and bonding between metal atoms. Therefore, the reason explains why the assertion is true.