@gelijah hi, that's exactly how I was thinking (by that, I mean the in conditional terms). But I am not sure why (B) is better than (A).

because, the stim says if hiccup (suff) --> ebola (nec). So how does it matter if other symptoms of Ebola do not appear in the account (especially when many other symptoms are mentioned in the accounts).

The way I am thinking is this:

The cause is ebola because account mention hiccup and if hiccup --> ebola. The only step where this argument could be weakened imo is how ebola and the impact of the epidemic are connected. Like prolly Ebola was present but not super devastating and there was another disease (with other corresponding symptoms) which caused the devastation. But I don't see why the fact that we don't see other symptoms of Ebola could be relevant (and it also seems unrealistic that ALL symptoms will be recorded in accounts!)

Again, I am not disputing (B), I was conflicted between and A and B; I just don't see how B is a stronger answer than (A).

Do you/others have thoughts?