The stems and leaves of many plants contain oxalic acid (H2C2O4) or sodium oxalate. A standard analysis for determining the amount of oxalate ion (C2O4 -2) in a sample is to precipitate oxalate out with the calcium ion. The reaction often involves the following reactants. Complete the following information for this reaction. Sodium oxalate and calcium chloride
Balanced Equation:
Total Ionic Equation:
Net Ionic Equation:

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.