# Liquid element(metal) among d-block is

$(a)\;Hg\qquad(b)\;Zn\qquad(c)\;Nb\qquad(d)\;Cd$

The element mercury is a dense silvery liquid at room temperature because its valence electrons have so much energy.
Hence the answer is $Hg$ as it exists as a liquid at room temperature.
Hence (a) is the correct answer.
edited Mar 20