Answer: Option D
:
D
The argument begins by offering one route through which a student can gain a coveted membership to the Bangalore club. For those aspirants who attended high school with a current member of the house and developed a strong social connection with that member before college, entrance into the club is easy. People who didn't attend high school with a current member can't easily attain membership through this route, but we were never told that his was the only way to easily get in to the club. The author concludes that the unconnected individuals will have difficulty joining the club, but that's only valid if the route the author describes is the only possible easy route. But the author never says that. (D) gets the major point the author fails to consider in issuing the conclusion: the possibility that there might be other ways to easily get into the club.
Option (a) First of all, those who attended high school with club members are not necessarily the same people who have forged strong social connections with them. So, the "many” referred to here may not even be relevant to the argument. Secondly, even assuming these guys are good high school buddies of the members, the author argues only about what conditions make for easy entry into the club, and need not consider the possibility that many high school classmates of the members would choose not to join.
Option (b) Associations with non-club members are not relevant to the argument and fall outside of its scope. Additionally, this Option discusses the long term benefits of such connections; which we are now worried about
Option (c) The relative difficulty of building these connections has nothing to do with their necessity for membership. This Option also shares with (B) an interest in non-club members, whom the author never mentions.