Examine the four jumbled sentences. Out of the given options, pick the one that gives their correct order.
A. They can travel to the airport by personal vehicle or registered cabs only.
B. Finally, all passengers are advised to strictly follow social distancing markers.
C. According to the Government guidelines, air travel is declared open from May 2020 for passengers.
D. Once there, they can walk in through the Entry Gates, which shall be kept open.