Which is the correct base pairing found in a normal DNA molecule?

Which one of the following statements is correct?

Which one of the following statements about animal cells and plant cells is correct?

Which one of the following is the correct sequence of organs that occur in the path of urine flow in human body?

Which one of the following salts is found in maximum amount in the human bones?

Which one of the following statements regarding bile secreted by liver is not correct?