Pictured here is the nitrogen cycle. The organisms that are responsible for
nitrification are most likely...

Option A, Bacteria

Explanation:

Nitrifying bacteria is a group of aerobic bacteria that converts ammonia in soil into nitrates so that it can be easily taken up by the plants. So basically, in this entire conversion bacteria’s of two distinct group are used – a) bacteria that convert ammonia to nitrites (such as Nitrosomonas, Nitrosospira, Nitrosococcus, and Nitrosolobus ); and b) bacteria that converts nitrites to nitrates

Hence, option A is correct

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.

if the type of the food available changes, then the frequency of beak types will change, because birds with beaks more suited to the available food will be more successful over time.