The second one I’m pretty sure !
The <em>magi</em> didn't, technically, <em>invent</em> anything. They were wise men or magicians and probably astrologers. Because astrologers watched the skies and could predict where the stars and planets would move to, they were considered to be able to foretell the future.
The sentence using the correct capitalization is the third:
"The Red Cross is a liaison for the families of soldiers stationed in other countries, acting as a go-between for separated spouses, parents and children."
Neither <em>liaison</em> nor <em>soldiers</em> need to be capitalized, since they are only common nouns, while the <em>Red Cross</em> is the proper noun of an institution and as such, it needs to have each word capitalized.
Latrine is a toilet or outhouse.
