Question

1. which of the following are features that help scientists classify annelids into their respective classes?

• presence of setae and septa
• presence of setae and parapodia
• presence of setae and tentacles
• presence of coelom and parapodia

Explanation:

To classify annelids (segmented worms) into classes, key features are considered. Setae (bristle - like structures) and parapodia (appendages for movement in some annelids) are important. Setae are present in many annelids, and parapodia are a distinguishing feature for classes like Polychaeta. The presence of setae and parapodia helps in classification. Other options: septa are more about internal segmentation in some annelids but not a main class - defining feature with setae; tentacles are not a primary class - defining feature for annelid classes; coelom is a general feature of annelids (they are coelomate) and not a key class - defining feature with parapodia.

Answer:

B. presence of setae and parapodia