Geometry

The answer is B. line.

Analyze each option:

A.Point: A point has no length, width, or thickness. It just represents a position in space. So a point cannot be straight and extend in both directions forever. Thus, “point” is not the correct answer.

B.Line: By definition, a line is straight and extends infinitely in both directions. This matches the description in the question. So “line” is a correct candidate.