Correct Answer: Mammal

Solution : The correct one-word substitute is the third option.

A mammal is a type of animal characterised by giving birth to live offspring and typically having mammary glands, which allow them to nurse their young with milk. This term encompasses all female animals that fit the description provided.

The meanings of the other options are as follows:

• A vertebrate is an animal that belongs to the subphylum Vertebrata, characterised by having a backbone or spinal column composed of vertebrates.
• A parasite is an organism that lives on or inside another organism (referred to as the host) and derives nutrients, shelter, or other benefits at the expense of the host. Parasites can cause harm or discomfort to the host organism without immediately killing it.
• Fauna refers collectively to the animal life or the entire collection of animal species found in a specific region or geological period.