Question

final review distinguishable from their ancestors because they all developed amniotic eggs for embryos. mammals are the newest class of phylum chordata. mammals developed the ability to produce milk, which sets them apart from their ancestors. which of the following is a feature of all mammals? horns produce milk cold blooded

Explanation:

The text states that mammals developed the ability to produce milk, which sets them apart from their ancestors and is a defining feature of all mammals. Horns are not present in all mammals, and mammals are warm - blooded, not cold - blooded.

Answer:

B. produce milk