Answer:
Red allele frequency will be highest in population II
Population III can undergo bottleneck effect
The frequency of the brown allele will least likely be altered in the population I
Explanation:
Population I -
Total population - 
Brown birds - 
Red birds - 
Population II
Total population - 
Brown birds - 
Red birds - 
Population III
Total population - 
Brown birds - 
Red birds - 
Frequency of red birds in population I

Frequency of red birds in population II

Frequency of red birds in population III

Red allele frequency will be highest in population II and it will be equal to
as compared to
in case of population I and III
Population III can undergo bottleneck effect because of smaller population size
The frequency of the brown allele will least likely be altered in the population that has highest brown individual , i.e population I
Cyanobacteria, also known as blue-green algae, are found in vast quantities in fresh and salt water. Cyanobacteria are able to conduct photosynthesis. By utilising energy from the sun, they produce carbohydrates from water and carbon dioxide. As a byproduct, they produce oxygen. So cyanobacteria provided oxygen to the atmosphere that allowed other lifeforms to develop.
The answer is A) air temperature.