The dendrites are covered with synapses formed by the ends of axons from other neurons. ... When neurons receive or send messages, they transmit electrical impulses along their axons, which can range in length from a tiny fraction of an inch (or centimeter) to three feet (about one meter) or more.
Graphite is well known to be pencil lead - You might actually learn this in Chemistry/Physical Science like we did!
Charcoal & coal you cannot use - you could but it'd be difficult and irritating.
Fullerene is the third form of carbon. It can be used for electronics AND medicine. Amazing right??
B) water cycle is the correct option
