As your heart rate increases, like when you exercise, your _ system makes sure nutrients get to your muscle cells _ and wastes are carried away _ too. (I attatched the article that goes with the question)

What is the main reason that attitudes are more often revealed in spoken rather than written language? a. in writing, we try to put the "best face" on what we write. b. we speak far more often than we write. c. in writing, we can more easily conceal our attitudes. d. in spoken language, we are often careless in our use of words.