Question

instructions: carefully read the below paragraph, then answer the following question. (1) some seemingly harmless substances can interfere with the way medicines work inside the body. (2) take grapefruit juice, for example. (3) it disrupts the action of enzymes that break down drugs in the small intestine before they are absorbed into the bloodstream. (4) therefore, taking a medication with grapefruit juice may cause the drug to enter the blood in dangerously high concentrations. (5) if this happens, not only is the drug less effective, but serious side effects can result. (6) many common medications, including antidepressants, antihistamines, and cholesterol drugs, are negatively affected by grapefruit juice. select the transitional expression that introduces an illustration. a of course b for example c therefore d anyway

Explanation:

"for example" is used to introduce an illustration. In the text, it is used to introduce grapefruit - juice as an example of substances that can interfere with medicine. Other options like "of course", "therefore", and "anyway" do not serve the purpose of introducing an illustration.

Answer:

B. for example