In this task, you are given a context and four options. Each option is a suggested ending for the context. You should read the context and pick the best ending for the context. Please answer with "A", "B", "C", and "D".

[header] How to groom a difficult dog [title] Choose a medication or calming aid. [step] There are a variety of products you can use to help calm your dog down for grooming. Some are medications that your vet would prescribe. <sep> (A) Others are herbal supplements you can buy over-the-counter, though they should not be used without consulting the vet first. Some common medications and calming aids include : [substeps] Benadryl melatonin acepromazine thundershirt [title] Ask your veterinarian about calming aids. (B) Try : [substeps] Salicylic acid: this has a calming effect on dogs, and it's safe for your dog. If your dog is coughing or heartsore, try these other medications. (C) [substeps] Heat and cold helps to calm your dog's respiratory system by flushing toxins from the body into the lungs. These can help to make your dog less nervous and less likely to feel nervous. (D) For example, you may need to get your dog to use a ppm spray. One medication and one calming aid is a pet treatment treatment.
A