1. Object C is made of metal
Object D is made of iron
2.The main difference between iron and metal is that iron is a chemical element that by mass, and is the most common element on planet Earth whereas metalmis a group of elements that have certain metallic properties such as ductility, malleability, conduction, etc.
3.Low resistivity or high conductivity, low temperature coefficient of resistivity, good thermal conductivity
that's all i know but hope it helps d•_•b
