What part of speech is request and be in this sentence. he made a request that there be an investigation

Which statement most strongly develops a positive tone? a. i was happy when i received my first paycheck for my hand work. b. winter break is approaching quickly, and i cannot wait to go shopping for gifts. c. going to the beach is one of my favorite activities; i love surfing and paddle boarding. d. a sense of accomplishment overwhelmed me as i stepped into into the stage that sunny, glorious day of graduation.