For a logic gate, if any input is high, the output is high. Which option best describes this behavior?

• A. All inputs must be 1 to produce a 1 output.
• B. Any input being 1 will produce a 1 output.
• C. Any input being 1 will produce a 0 output.
• D. No input being 1 will produce a 1 output.

Answer: (B)

The behavior described is the OR operation: the output goes to 1 whenever any input is 1. This means at least one high input is enough to make the output high, and the output stays 0 only when all inputs are 0. For example, with two inputs, if one is 1 and the other 0, the output is 1; if both are 0, the output is 0; if either or both inputs are 1, the output remains 1. That’s why the description “any input being 1 will produce a 1 output” best matches OR behavior. The other descriptions don’t fit: requiring all inputs to be 1 describes an AND function; stating that any input being 1 produces a 0 output would be the opposite of OR; and saying no input is 1 produces a 1 output contradicts the OR truth table.