Explanation:
they are independent systems, so in case of an emergency both systems will activate.
this is like rolling 2 dice and asking for the probability that both will show 1.
the probability that both will fail is the product of the individual probabilities for failure :
0.01 × 0.03 = 0.0003
so, the third answer option is correct.
FYI - the probability for 2 dice to both roll 1 is
1/6 × 1/6 = 1/36