Question

Which of the following mammals lacks corpus callosum?

• A. Macaca
• B. Macropus
• C. Ornithorhynchus
  
• D. Both B and C

Answer 1

The correct option is D Both B and C

Corpus callosum is the connective band that joins the two hemispheres of the brain. It arises from the brain and brain stem. It is mainly present in the most evolves mammals like placental mammals but absent in monotreme and marsupials. But Platypus or Ornithorhynchus comes under monotreme which are the primitive mammals that lay eggs and Macropus is belonged to marsupial.
So, the correct answer is option D.