Question

[BWS.03]A scientific theory is proposed after several valid investigations. This makes scientific theories

elaborate descriptions of observations

the most powerful explanation scientists have to offer

unchangeable by other scientists over a period of time

unacceptable to a majority of scientists

Answer 1

You have to talk these things out. Just create a short comment for each.

C and D are just silly.
A cannot be entirely ruled out. It MAY be elaborate.
B seems promising.