The resulting tree looks like below tree :
4
/ \
3 6
/ / \
2 5 8
Finding 4 now takes one comparison (with the root), finding 3 and 6 take two comparisons, and finding the other nodes takes three comparisons. Hence option I is correct .
There are three leaf nodes and three interior nodes. Option II is correct .
If 7 is inserted, it will go onto a new level, as the left child of 8. This makes option III false .