Answer the following question given this paragraph: 

Mammals have separate sexes and reproduce sexually. They produce eggs or sperm and must mate in order for fertilization to occur. A few mammals are oviparous. They lay eggs, which later hatch. These mammals are called monotremes. Most mammals are viviparous and give birth to live young. These mammals are either placental mammals or marsupials. Placental mammals give birth to relatively large and well-developed fetuses. Marsupials give birth to smaller, less-developed embryos. In both placental and marsupial mammals, the young grow and develop inside the mother’s body in an organ called the uterus. At birth, they pass through a tube-like organ called the birth canal, or vagina.


Q: Mammals that lay eggs are called what?

 Choices:

- viviparous

- herbivores

- marsupial

- monotremes

A:
monotremes
