A researcher may decide that a taxon is actually polyphyletic if

If the two organisms descended from different ancestors

Explanation:

In taxonomy, organisms are placed into different groups called taxon.This is usually on the basis of their shared characteristics.

Based on characteristics, polyphyletic taxon can be formed.

Polyphyletic means unrelated organisms from different recent ancestor.

However, a researcher may decide that a taxon is actually polyphyletic if the organisms in the organisms placed in that group do not share a common ancestor.

the correct answer is option b

behavioral response need communication and thus co-ordination at several levels such as interaction among cells, organ system and the entire organism.

behavioral response produces both internal and environmental stimulus.