Answer:
The answers are B and D.
Step-by-step explanation:
Since Natalia wants to support the idea that a stray or rescued dog has many advantages than a bought one, options A, C, and E wouldn't be good for her thesis since they express negative things about adopting or rescuing a dog.
On the other hand, option B mentions that an adopted dog may already have had necessary medical procedures, meaning that it would save time for the new owner. Option D says that an adopted dog may already have been trained at the animal shelter or in its previous home so it also would be very helpful for its new family.