The addition of a catalyst in a chemical reaction
(a) increases the concentration of products at equilibrium.
(b) increases the fraction of reactant molecules with a given kinetic energy.
(c) provides an alternate path with a different activation energy.
(d) lowers the enthalpy change in the overall reaction

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

if it's not useful, feel free to report for mistake in answer.

metric time was an attempt to create a standard unit of time based off of 10, but it never took off an is not included in the metric system (si)