If experiments support a hypothesis, why is the hypothesis still not considered proven?

The correct answer would be because of a better explanation might exist.

Explanation:

The hypothesis is an idea that is a matter of question and explanation on the basis of the experimental studies or experiments. If experiments support any hypothesis it might still be questionable and there might be a better explanation for this.

Thus, the correct answer would be - because there might be a better explanation for it.

burning of wood and coal

explanation:

the panel also concluded there's a better than 95 percent probability that human-produced greenhouse gases such as carbon dioxide, methane and nitrous oxide have caused much of the observed increase in earth's temperatures over the past 50 years.