An example of a consumer buying a product directly from a supplier is purchasing an airline ticket through an online travel agency purchasing an airline ticket through a travel agency purchasing an airline ticket through an airline's web site purchasing an airline ticket through a cruise liner

The only way of buying directly from a supplier is cutting the intermediaries. In this case the travel online agency, the travel agency, and the cruise liner are all intermediaries since they are not the airline. Purchasing the ticket through the airline’s website is, therefore, the correct answer.

this is b. how railways dealt with people riding the trains without paying

faithful servants eumaeus and philaetius:

his ragged vest then drawn aside disclosed the sign conspicuous, and the scar exposed: eager they view'd, with joy they stood amazed with tearful eyes o'er all their master gazed:

these servants know ulysses by the scar he got when he was a child - so when he showed them the mark, they immediately knew this is truly their master and they hugged him, finally starting to believe his words.