When a person has pneumonia, fluid accumulates in the alveoli. This fluid accumulation directly results in which of the following problems?

Here are the answers to your questions:

Question 1:
PKU (Phenylketonuria) is a genetic disorder. Genetic disorders are typically caused by changes in the DNA sequence of a gene, known as mutations. These mutations alter the gene's function, leading to the condition.
The correct option is A) A mutation occurred in the PAH gene.

• A mutation in the PAH gene prevents the body from properly breaking down phenylalanine, leading to PKU.

Question 2:
The alveoli are tiny air sacs in the lungs where the exchange of oxygen and carbon dioxide between the air and the blood takes place. When fluid accumulates in the alveoli due to conditions like pneumonia, it creates a barrier that hinders this exchange.
The correct option is D) reduced gas exchange between the lungs and the blood.

• The fluid makes it more difficult for oxygen to diffuse from the alveoli into the bloodstream and for carbon dioxide to diffuse from the blood into the alveoli to be exhaled.