C) the changes reflect...
The first thing that the farmer should do is formulate a hypothesis in which he will make intelligent guesses on what is happening or develop a theory of which would explain what is happening. It is the first step in scientific investigation in order to formulate questions of why weeds that are sprayed does not die. After this, it is only then the farmer should experiment and after that, he should finalize his findings as it is its conclusion to the problem.
"Identical twins come from a single fertilized egg, or zygote, that splits in two. Both halves contain the same DNA and eventually form two fetuses. But clones are formed in a different way. The first step in making a clone is to empty the DNA out of a fertilized egg".
-Google
Producers, because they're the start of the food chain and without them there will be no food chain.