Answer: The shortest living man at that time had the height that was more extreme.
Explanation:
We will z scores to solve this exercise. The formula we need is:

Where
is the raw score,
is the mean and
is the standard deviation.
We know at that time heights of men had a mean of 170.53 centimeters and a standard deviation of 5.91 centimeters, then:

Knowing that the tallest living man at that time had a height of 230 centimeters, we get:

And knowing that the shortest living man at that time had a height of 91.3 centimeters, we get:

Based on this, we can conclude that the shortest living man at that time had the height that was more extreme.