In the following passage, some words have been deleted. Read the passage carefully and select the most appropriate option to fill in each blank.

It is important to (1)________ a healthy lifestyle to maintain good physical and mental well-being. Regular (2)________ helps improve cardiovascular health and boosts the immune system. Eating a balanced diet rich in (3)________ vitamins and minerals is crucial for overall health. Additionally, (4)________ stress through activities like yoga or meditation can enhance mental clarity. Getting an adequate amount of (5)________ each night is essential for restorative activity and optimum bodily functions.

Select the most appropriate option to fill in blank number 2.

The correct option for blank number 2 is exercise.

Let's analyze the passage and the context of the sentence containing blank (2):
"Regular (2)________ helps improve cardiovascular health and boosts the immune system."

Now, let's look at the given options to find the most suitable noun that fits grammatically and contextually:
1. exalt: This is a verb meaning to praise or raise in rank, which does not fit grammatically as a noun following "Regular" in this context.
2. exclaim: This is a verb meaning to cry out suddenly, which does not fit contextually or grammatically.
3. exertion: This is a noun meaning physical or mental effort. While related to physical activity, "regular exertion" is less idiomatic in health contexts compared to "regular exercise", and exertion can sometimes refer to strain rather than healthy activity.
4. exercise: This is a noun referring to physical activity performed to sustain or improve health and fitness. "Regular exercise" is a standard collocated phrase that perfectly fits the description of helping to "improve cardiovascular health and boost the immune system."

Therefore, exercise is the most appropriate option to fill in blank number 2.