Self-study
On a short trip a driver is more likely to have an accident if there is a passenger in the car, presumably because passengers distract drivers. ████████ ██ █ ████ ████ █ ██████ ██ ████ ██████ ██ ████ ██ ████████ ██ ███ ██████ ██ ██████
"Surprising" Phenomenon
Why are drivers with passengers more likely to get in accidents on short trips but less likely to get in accidents on long trips?
Objective
Any hypothesis explaining this phenomenon must state some difference between short and long trips. This difference must include a distinction between solo drivers and drivers with passengers that explains why carrying a passenger increases accident risk on long trips but decreases it on short trips.
4.
Which one of the following, ██ █████ ████ █████ ██ ███████ ███ █████ █████████ ██████
a
People are much ████ ██████ ██ █████ █████ ██ █████ █████ ████ ██ ████ ██████
This would explain a discrepancy between the total number of accidents in each category, but not different likelihoods of getting in an accident.
b
Good drivers tend ██ ████ ████ ████ █████ ████ ███ ████████
This does not account for a passenger changing the probability of getting in an accident. It explains a phenomenon different from the one described.
c
The longer a ███ ████ ███ ███ ████ ██████ █ █████████ ██ ██ ████ ███ ██████ ████████ ██████████
This explains why having a passenger lowers the probability of an accident during a long trip but increases it during a short trip. Passengers on short trips distract the driver, while passengers on long trips keep the driver alert.
d
On a long ████ ███ ██████████ ██ ██ ████████ ████ ███ ████████ ████ ████ ██████████ ██████████
This states no difference between cars with passengers and cars with no passengers. For the sake of the discrepancy, cars with multiple passengers fall into the same category as cars with one passenger.
e
Most drivers take ███ ████ █████ █████ ████ ████ ██████
This would explain a higher number of accidents on short trips, but not the phenomenon described. It does not explain why a passenger raises the accident probability in some cases but lowers it in others.