Yeah, I couldn't find the specific wording right now and whether there was some sort of plausible play with the word "planned". This question is also translated.
Actually I managed to find out the exact wording of the question, it was fairly different from what I remembered:
What affects the duration of a planned journey?
a) Length of the journey.
b) Maximum speed in few lone sections of the journey.
It uses checkboxes, so you can check both.
They expect you to check only a), but b) is in my view also logically correct answer as if at any section even if it's shorter than 1 metres, if your max speed nears 0, duration of your journey will reach infinity. But it is worded in such a way that most people will get the hint that B) should not be checked.
While we are at looking at it pedantically (keeping also in mind that you said it's translated) I think their expectation of the answer is fair and they give more than a hint on it as well. Like you'd be stupid not to know what answer they want you to check.
"few" and "lone sections". As in statistically irrelevant. The assumption is that people 'get' for example (and its being taught over and over in driving school too) that if you speed to get through one traffic light in the city you'll not make it through the next one anyway and thus not really be faster. On the highway if you only speed once or twice for a short lone section you won't really notice in the end.
You don't even have to come at it with a nerd mathematicians mind and play tricks like Max speed near zero (not a realistic scenario so not something a driving exam would ask but definitely a fun scenario in a math lecture at university maybe). I can think of multiple sections in my city where speeding through the right traffic light when it's "cherry green" will net you a significant advantage because of the awful street and intersection layout and traffic light phases in that area. If you do the same just one traffic light after it though it won't help you at all because the next light will catch you unless you really want to cause an accident.
And if you are driving a 500km+ route and you can "speed" through it at 160+ km/h for a significant portion of it vs. going 120 that will save you a noticeable amount of time on the journey. This assumes something like Germany and your route being in parts with not many speed limits and not too much traffic so that you can comfortably cruise at 160 to 180 vs. arriving as a nervous wreck close to a heart attack because of all the near crashes from slowing down for the grandma going 100 switching to the left lane a few car lengths in front of you.
