Tar allows a. carcinogens to attack the immune system b. carcinogens to stick to pulmonary cells c. carcinogens to multiply in the liver d. all of the above

Iwould say the answer is: a. carcinogens to attack the immune systemhope that : p

Covalent bond is the correct answer

Some of her  assignments would be creation of drugs. she is a medical chemist after all so she'd need to have the necessary knowledge to make medicine which can later be sold in a pharmacy