In the United States Congress, how long is a single term of office for a member of the House of Representatives?

Introduction / Context:
The United States Congress is a bicameral legislature consisting of the House of Representatives and the Senate. The length of terms for members of each chamber is fixed by the Constitution and affects how often elections are held. This question focuses on the House of Representatives and asks how long one term lasts for a member of that chamber.

Given Data / Assumptions:
- The question specifically concerns the House of Representatives, not the Senate.
- Four different possible term lengths in years are given as options: 2, 4, 5 and 6 years.
- Only one of these matches the constitutional term length for House members.

Concept / Approach:
According to the United States Constitution, members of the House of Representatives serve two year terms. All seats in the House are up for election every two years, which means that the House can change significantly in each election cycle. This short term is designed to keep representatives closely accountable to the people.

Step-by-Step Solution:
Step 1: Recall that the House of Representatives is the lower chamber of Congress and is directly elected from smaller districts. Step 2: The Constitution clearly sets the term of a Representative at two years. Step 3: The Senate, by contrast, has six year terms with one third of Senators elected every two years. Step 4: Therefore, 2 years is the correct term length for House members, and the other numbers correspond either to Senate terms or do not apply.

Verification / Alternative check:
You can check any basic civics or American government textbook, which will state that elections for the entire House of Representatives are held every two years. This confirms that the term of office for a Representative is two years, unlike the longer senatorial terms.

Why Other Options Are Wrong:
- 5 years: Not used as a standard term length in either chamber of Congress.
- 4 years: This is the length of the presidential term, not the House term.
- 6 years: This corresponds instead to the term length of a United States Senator.

Common Pitfalls:
A common confusion is to mix up the term lengths of different offices, particularly the presidency, the Senate and the House. Another error is to assume that all national legislators serve longer terms, whereas the design of the House deliberately uses shorter terms to maintain close electoral contact with voters.

Final Answer:
A member of the United States House of Representatives serves a term of 2 years.