In a cladogram, when does a group of organisms branch off? when a new trait evolves when an ancestor becomes extinct when it is discovered when it becomes large enough

When a new trait evolves (option A)

Cladogram is an image diagram that shows connections/relationships between different organisms. It shows the evolutionary relationship between the organisms. The tree like structure may change when a node is placed in cladogram, that point is also known as the point of divergence.The diagram illustrates lines, which branch off in different directions and which end up at a clade. a group of living organisms that share a last common ancestors is defined as the clade.

Cladograms are made by grouping the similar organisms together and they are grouped based on the characteristics that they possess.  

a: the sheep and waste material both release carbon into the atmosphere.