Instead of blaming an automobile accident on driver error, insurance c

Responding to a pm:

I am not happy with both (D) and (E).

Here is the argument:
Insurance companies blame drivers for accidents and punish them.
Instead, they should try to figure out why the error was made by analyzing flaws in road design, automobile designs and in criteria to determine eligibility for a driver's license.

Conclusion: Investigation of roads, automobiles and drivers is necessary to issue guidelines to prevent future accidents.

(D) is not an assumption. "Investigation of automobile accidents" is too generic. We don't know what it means. Even if we assume that it means "try to figure out why the error was made by analyzing flaws in road...", we are already given this. We are given that "investigation" is necessary to effectively issue guidelines to prevent future accidents.

(E) is a little far fetched. The argument presupposes that people who make driving errors may not be eligible to drive i.e. they may be bad drivers and may need retraining. Now we don't know whether those drivers repeat those errors, commit other errors or other drivers commit the same errors. All the argument is saying is that we will not be able to prevent accidents by punishing the drivers alone.