Question

multiple choice question
monotremes are mammals that ————, while marsupials and placental mammals ————.

o lay eggs; are live - bearing
o have mammary glands; lack mammary glands
o are live - bearing; lay eggs
o lack mammary glands; have mammary glands

Explanation:

Monotremes are unique mammals that lay eggs (e.g., platypus). Marsupials (e.g., kangaroo) and placental mammals (e.g., humans) give birth to live young. All mammals have mammary glands, so options related to mammary glands being absent in some groups are incorrect.

Answer:

lay eggs; are live - bearing