Answer:
The correct answer would be rhesus monkey.
Step-by-step explanation:
The newly discovered organism has four legs, mammary gland, and placenta. According to cladogram paired legs are at started just before the bull dog, mammary glands developed before koala and placenta just before rhesus monkey. So, the only animal with all these three characters to the newly discovered organism is rhesus monkey.
Thus, the correct answer is the rhesus monkey.