If seed 15 won the tournament then what is the minimum number of upsets caused by him?

If all the matches in stage 1 is an upset except the last match where seed 32 won, then in stage 2 seed 32 is the highest seeded player who can win the tournament without causing an upset.

Seed 9 played with seed 56 in stage 1, with seed 24 in stage 2, But seed 11 can reach the final if he beats seeds 6, 3 and 2 in stage 3 4 and 5 respectively.

Total number of matches is 32 + 16 + 8 + 4 +2 + 1 = 63
Or else since total number of players is 64 hence number of matches must be 64 - 1 = 63

Since 64 = 2⁶ hence we will have total 7^th stages in the tournament with last 7th stage is the final match.

Lets eliminate options one by one-
Option A: Child is hungry, So, from (ii) child is crying, but we cannot say anything about the child liking milk or not.
Option B: A child is crying, but from this we cannot say anything regarding the child being hungry or unhappy.
Option C: The statements are not speaking about the happy child.
Option D: Unhappy children are hungry and hungry children cry. So choice (D) is most logically supported.

From the table F won 4 matches.

From the table G lost 4 matches.

From the table E won against C and G

C and E won 2 matches.

2 teams won 2 matches each