Islets of Langerhans are present in

Which one of the following statements is incorrect?

Select the correct options for the pancreas:
$I-$ Compound gland
$II-$ Elongated organ
$III-$ Situated between the limbs of the $U$-shaped duodenum
$IV-$ The exocrine portion secretes an acidic pancreatic juice containing enzymes
$V-$ The endocrine portion secretes hormones,insulin and glucagon

Which type of bond is present in the structure of hormones secreted by the pancreas?

What is the normal percentage of sugar in human blood (in $\%$)?

What is the main function of insulin?