I think answer should be D because spanning tree will include all vertices of graph .
Option A is wrong because vertex N must have odd degree but not neccessarly 1 . since in a graph no. of odd degree vertices must be even and in given graph all have even except 1 . thats why
option B it is not fixed that graph must be connected it may be a is connected .
Option C if graph is disconnected then there is no path ib between 1 And N .
Correct me if i am wrong ;?