Engineers consider three methods for sending a distress signal from a spacecraft in low-Earth orbit to a submarine 200m below the ocean surface:
(1) an acoustic whistle produced inside the spacecraft,
(2) a beam of visible green laser light, and
(3) a radio-frequency transmission at 100MHz.
Which ranking correctly orders the methods from most to least likely to deliver any portion of the signal to the submarine?
a) 3, 2, 1
b) 2, 3, 1
c) 1, 3, 2
d) 2, 1, 3