Option 2 is the correct answer, which states that Azolla, Cyanobacteria, and Azospirillum have the ability to fix atmospheric nitrogen.

Let`s break down each of the options for a better understanding:

Option 1 includes all four choices (1, 2, 3, 4). This is incorrect because E. Coli does not have the ability to fix atmospheric nitrogen. While E. Coli is a common bacteria that resides in the intestines of humans and animals, it does not possess the necessary enzymes to fix nitrogen.

Option 2 includes choices 1, 3, and 4 (Azolla, Cyanobacteria, and Azospirillum). This is the correct answer because all three of these organisms have the ability to fix atmospheric nitrogen.

Option 3 includes choices 1, 2, and 3. This is incorrect because Azospirillum is missing from the options.

Option 4 includes choices 2 and 3 (E. Coli and Cyanobacteria). This is also incorrect because E. Coli does not have the ability to fix atmospheric nitrogen.

Therefore, option 2 is the correct answer.