A survey report states that those who undertake physical exercise for at least half an hour a day are less prone to heart ailments than those who do not exercise. Based on this statement, which of the following conclusions is definitely valid?

Introduction / Context:
This question is based on interpreting a survey statement about exercise and heart health. The survey claims that people who exercise daily for at least half an hour are less prone to heart ailments. We must decide which conclusion reflects the information correctly without overstating or contradicting it. The challenge is to respect the wording of the survey and avoid extreme interpretations.

Given Data / Assumptions:

• The survey covers people who undertake physical exercise for at least 30 minutes a day.
• These people are reported to be less prone to heart ailments than those who do not exercise.
• The statement relates exercise to reduced risk of heart disease, but does not give exact percentages.
• The comparison is between exercising people and non exercising people.

Concept / Approach:
From the survey, we can safely infer that regular moderate exercise is beneficial for heart health. That is, exercise is an important factor in a healthy lifestyle. However, the survey does not prove that everyone without exercise will definitely get heart disease, nor that everyone with exercise will definitely be free from heart issues. So conclusions that make absolute claims about all individuals in a category are too strong and are not justified.

Step-by-Step Solution:
Step 1: The phrase less prone to heart ailments means exercise reduces the likelihood of heart problems compared to not exercising.Step 2: Exercising at least half an hour daily is a moderate level of physical activity. The data suggest this moderate activity is associated with better heart health.Step 3: Thus, it is reasonable to conclude that moderate physical exercise is a necessary component of a healthy lifestyle, particularly for heart health.Step 4: The conclusion that all people doing desk bound jobs definitely suffer from heart ailments goes far beyond the survey, which only talks about relative risk, not certainty.Step 5: There may be individuals with desk jobs who still exercise regularly and maintain good heart health. The survey does not claim the opposite.Step 6: So any conclusion that claims all desk bound workers definitely have heart problems is unsupported and incorrect.

Verification / Alternative check:
Imagine two groups, one that exercises daily and one that does not. The survey says the first group is less prone to heart disease.This directly supports the idea that exercise is important for health but does not guarantee outcomes for every single person.The survey also does not mention job type directly, so conclusions about all desk workers are beyond its scope.

Why Other Options Are Wrong:
Option b combines a reasonable statement about exercise with an extreme statement about desk workers which the survey never supports.Option c is wrong because it treats lack of exercise as a guarantee of heart disease, which is not stated.Option d, that neither conclusion can be drawn, ignores the clear trend linking exercise and reduced risk.Option e contradicts the basic message of the survey that exercise reduces risk, so it is clearly incorrect.

Common Pitfalls:
Confusing less prone with never or always, which changes a probabilistic statement into a certainty.Adding new conditions such as job type that are not mentioned in the original survey.Assuming that one factor like exercise explains all cases of heart disease, which oversimplifies health science.

Final Answer:
The conclusion that is safely supported by the survey is that Moderate physical exercise is necessary for leading a healthy life, especially for reducing the risk of heart ailments.