The correct sentence would be... " I don't understand how we could disagree! We both witnessed the same accident!" You need a capital I and a capital W at the start of your second sentence.
The question asks us how could we disagree. We just witnessed the same accident. Out of all the answer choices A seems reasonable because we need to all acknowledge that people create different perspectives and see things differently.
"Agar agar" is a natural polysaccharide produced by marine algae and is the most commonly used solidifying agent added to media (end concentration usually 1.5 % w/v).
