Final answer:
There are 100 U.S. senators, with each state electing two. Senators serve six-year terms with elections staggered over even years.
Step-by-step explanation:
The correct answer to the question "How many U.S. senators are there?" is one hundred (100). Each of the fifty states in the United States elects two senators, resulting in a total of 100. These senators serve six-year terms, and one-third of them are elected during each midterm and each presidential election year. The President Pro Tempore is the presiding officer in the Senate's daily proceedings. In contrast, the House of Representatives consists of 435 voting members, with the Speaker of the House presiding over the House.