Testing Connectivity/LoopBack Address

Question

A system is connected to n/w 192.168.1.0 with IP 192.168.1.2 . System will check its connectivity to Internet by sending control packet

SIP- 192.168.1.2

DIP- ?

1. 192.168.1.0
2. 192.168.1.1
3. 127.1.1.1
4. 127.0.0.0

Confused with the following  - The ans given is 127.1.1.1 Should not the ans be 192.168.1.1  since  127 is a loopback address and used to test if all the layers are working correctly (self-connectivity) ? 

Nothing going through the loopback adapter goes out to the Internet, or leaves your system. The loopback adapter is completely contained within the system

Comments

u have to test ur own system means self connectivity then why u want to appear on internet and tell this to everyone.....thats why we use loop back address..it goes till DLL and then returns back without appearing on network..in this way we can test whether NL and other layers are working or not...given answer is right..

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Why 4 is wrong?

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practically its possible but from the very starting we have neglected all 0s and all 1s networks of class A..
so except these anything with 127 can be used...infact 127.1.1.1 is also not right theoretically...

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@sudsho Thank you for the help. Not sure if I was overthinking but while solving I was struck with the following thought -

Question says 'How will System check its connectivity to the Internet?'

As you mentioned loopback will return from DLL. But if the LAN segment to which it is connected or physical medium is down that would not imply that he is connected to the Internet right? As in that case the host cannot send packets to any other host.

Answer 1

3)127.1.1.1 is used for loop back address ,so it may be the right option(but this can testify ur layers only not the connectivity to the internet). because u can run loopback address even without having any internet connection.

but bigger question is that why else are wrong?

1)198.168.1.0 this one is surely not the answer because this is not a host or system address it is a network id so it cant be correct.

2)198.168.1.1 is wrong because when u send control packet to that host it does not go outside lan network as it is a private ip

4)127.0.0.0 this is again treated as network id so cant be the answer

but let if another option is given such as 192.168.1.2 in which source and destination are same then it is the sure right answer because it can be only done if u r connected to internet unless this will fails giving message destination unreachable.

i done all this practically but then also correct me if i was wrong!!!