This question has been in the bank for some time, with various rewrites reported. This version states that "all radios were destroyed." With this in mind, let's examine the answer options:

Try to contact ATC via CPDLC. There is more information on CPDLC below, but this is certainly one of it's functions. Assuming that the CPDLC is not included in "all radios" being destroyed then this is the correct answer.

Try to contact ATC via ADS-B. ADS is for reporting aircraft position etc, not for communications. It does have an emergency function however, so is a possible answer, but is not as strong an option here as using CPDLC.

You should not contact ATC. Obviously you should try to, being able to in this situation is something else.

Try to squawk "7600" on your mode A transponder. 2 things here: 7600 is for radio problems, which you certainly have but squawking "7500" for unlawful interference or indeed "7700" for emergency would be better options. Secondly, were the transponders destroyed as part of "all radios"? If not, it's still a wrong answer due to the choice of squawk code.

CPDLC is covered fully in the Instruments syllabus but here is more information…

Controller Pilot Datalink Communications (CPDLC) using the FANS 1/A network has become the primary means of communicating with ATC in oceanic regions around the world and is also implemented in several domestic regions as well. One function of FANS CPDLC no crew ever wants to have to use is emergency reporting. During an emergency, the flight crew would normally revert to voice communications. However, the crew may use CPDLC for emergency communications if it is either more expedient or if voice contact cannot be established.