Aparticle system is a. a collision between many different particles that creates a sparkling effect b. a group of particles that work together to create an image with lots of similar but separate moving parts c. an event that has many different conditions d. a group of objects that all have path movement that loops and reverses when they reach the end of the path

The answer is "B".

A particle system is "a group of particles that work together to create an image with lots of similar but separate moving parts".

Particles are little, basic pictures or networks that are shown and moved in extraordinary numbers by a particle system.  

Every particle represents a little segment of a liquid or amorphous substance and the impact of the considerable number of particles together makes the impression of the total element. Utilizing a smoke cloud for instance, every molecule would have a little smoke surface taking after a minor cloud in its own right. At the point when a large number of these little mists are orchestrated together in a zone of the scene, the general impact is of a bigger, volume-filling cloud.  

Every particle has a foreordained lifetime, regularly of a couple of moments, amid which it can experience different changes. It starts its life when it is created or discharged by its molecule framework. The framework produces particles at irregular positions inside a district of room molded like a circle, half of the globe, cone, box or any subjective work.

a woodchuck could chuck 5 pieces of wood