Hi Ace22704,
Answer - natural observation
I think this experimental method is a better option because its in a natural environment where the kids dont know whats happening unlike the suveys where you ask them questions which is probably a bad idea because they might feel scared and just change their minds.
15. C
16.B
17.H
18. A
19.E
20.D
21.G
22.F
I think this is correct sorry if any are wrong