A clade is
- A
An ancestor and SOME of its descendants (a paraphyletic group)
- Bcheck_circle
An ancestor and ALL of its descendants (a monophyletic group)
- C
Two species sharing convergent traits (a polyphyletic group)
- D
A lineage and its sister group combined (a sister-clade group)
Explanation
Monophyletic groups include only descendants of one common ancestor. Modern systematics aims for clades over arbitrary groupings.