Another of Hoyle's arguments can be summarized as follows: on Earth, all the natural occurrences of methane that we know of are associated with "methanogens" (methane-producing bacteria). But there is evidence that methane is also present in some inter-planetary material in comets, for example. Therefore, it is likely that methanogens are present in these materials also. Which of the following is true of this argument?
A) It would be strengthened by the discovery of other compounds which occur both on earth and in comets, and whose terrestrial occurrence is strongly correlated with bacterial action.
B) Since this argument appeals to no analogies between terrestrial and extra-terrestrial phenomena, it does not need any explanation of how methanogens synthesize methane.
C) This argument has no evidential force with respect to the extra-terrestrial existence of bacteria unless it can be supplemented with an explanation of the process by which terrestrial bacteria synthesize methane.
D) The plausibility of Hoyle's conclusion would be seriously weakened if on-site explorations of other planets in our solar system were to reveal the existence of methanogenic bacteria there.
E) It would be strengthened if it were discovered that methane is generated in Antarctica, without bacterial action, at low temperatures, which approximate those of comets far out in the solar system.
A) It would be strengthened by the discovery of other compounds which occur both on earth and in comets, and whose terrestrial occurrence is strongly correlated with bacterial action.
B) Since this argument appeals to no analogies between terrestrial and extra-terrestrial phenomena, it does not need any explanation of how methanogens synthesize methane.
C) This argument has no evidential force with respect to the extra-terrestrial existence of bacteria unless it can be supplemented with an explanation of the process by which terrestrial bacteria synthesize methane.
D) The plausibility of Hoyle's conclusion would be seriously weakened if on-site explorations of other planets in our solar system were to reveal the existence of methanogenic bacteria there.
E) It would be strengthened if it were discovered that methane is generated in Antarctica, without bacterial action, at low temperatures, which approximate those of comets far out in the solar system.
