Answer:
I think it may be D ( it suggests a tone of loving concern )
I will only revise it, but not edit it.
It may assess that every year 26 million animals in the United States would continuously utilize similarly as a pet. Animals are being used to test scientific developments and commercial products. New medical treatments are tested on animals to verify the toxicity of new medications or the safety of a human-used product. The healthcare and the commercial industries are also turning to the animal experiments for these understandings.
