1. Natural immunity: Getting an illness, producing antibodies and recovering from it.
2. Vaccinations.
3. Antibodies from the mother.
Can't think of a fourth one.
the four types of living things is animals,plants,people,matters
Humans
There are four types of pneumothorax. The types are: traumatic pneumothorax, tension pneumothorax, primary spontaneous pneumothorax, and secondary spontaneous pneumothorax.
There are four main classes of animals: Mammals (Mammalia), Birds (Aves), Reptiles (Reptilia), and Fish (Chondrichthyes, Agnatha, Placodermi, Actinopterygii, Sarcopterygii).
birds,insects,bugs,animals
In Texas there are four elections, which are Primary elections, General elections, Special elections and others.
Compact camera, superzoom camera, System camera and DSLR
What are the four most common types of shopping centers? These primary shopping center types are: The corner store, convenience center, neighborhood center, community center, regional center, and the lifestyle (town) center.
there are actually 5 types. bird, fish, amphibian, reptile, and of course mammal
The four tastes detected on the tongue are: Salty, sweet, sour, and bitter.
Thirty-four US states and the District of Columbia hold presidential primary elections. There are three types of primaries, open, closed and mixed.
the four types of sources are books, internet, library,files I know there is general, primary and secondary, Not sure about the last.