Final answer:
The conclusion that people with an MBA earn an income 70% higher than those with an undergraduate degree does not follow from the given information.
Step-by-step explanation:
The conclusion that people with a master's degree in business administration (MBA) earn an income on average 70% higher than people with just an undergraduate degree does not follow from the given information. Although it is true that earning an MBA can lead to an increase in income, the specific percentage increase mentioned in the question is not supported by the data provided. Additionally, the statement that MBA students from top business schools earn an income on average 50% higher than the average income of people with MBAs is not directly relevant to the comparison of income between undergraduate and MBA degree holders.