Combine Lead (II) nitrate with Potassium Iodide solution

When you add lead nitrate to potassium iodide, their particles combine and create two new compounds, a yellow solid called lead iodide (Pbl2) and a white solid called potassium nitrate (KNO3). Yellow clouds indicate that the chemical change has taken place.

i just got this problem. it's 90.3

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.