Fill up the blanks in the following paragraph by selecting the correct option The vascular

Fill up the blanks in the following paragraph by selecting the correct option The vascular system of frog is well-developed `ul("I")` type. The blood vascular system involves heart, blood vessels and blood. Heart has 3 chambers, two atria and one ventricle and is covered bu a membrane called `ul("ii")`. A triangular structure called `ul("iii")` joins the right atrium.