What is a conductor?
1. An object that does not transfer heat well
2. An object that transfers heat well
3. A living organism
4. Part of the human body

2. An object that transfers heat well

Explanation:

Conductors has closer molecules in which can bump into each other easily to help transfer thermal energy. Examples are iron, steel, gold, copper, and other metals.

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.