The main difference among the four soil types is the size of the grains (particles) that make up the soil.
a. true
b. false

True                                                                                                                                              hopes this helps

The truman doctrine was an american foreign policy whose stated purpose was to counter soviet geopolitical expansion during the cold war. it was announced to congress by president harry s. truman on march 12, 1947, and further developed on july 12, 1948, when he pledged to contain threats to greece and turkey