हड्डी की बाहरी सतह एक घने रेशेदार सुरक्षात्मक आवरण से ढकी होती है जिसे क्या कहा जाता है?

Choose the correct statements regarding frog's anatomy: A. Hepatic portal system is the special venous connection between liver and intestine. B. There are ten pairs of cranial nerves arising from the brain. C. The ureters and oviducts open separately into the cloaca in female frogs. D. Hind-brain consists of cerebellum and medulla oblongata. E. Sinus venosus joins the right atrium of heart. Choose the correct answer from the options given below:

Male frogs can be distinguished from female frogs due to the presence of: A. Bulging eyes B. Vocal sacs C. Webbed digits in feet D. Copulatory pad on first digit of fore limbs E. Olive green-coloured skin with dark irregular spots Choose the correct answer from the options given below: