Choice A is the correct answer. Combine the two conditions.

1. Below $y=3x$: $y < 3x$
2. Above $y=3x-4$: $y > 3x - 4$
3. Combine: $3x - 4 < y < 3x$

?�� Strategic Tip: This describes a band between two parallel lines.

Choice B is incorrect because it implies $3x < 3x - 4$, which is impossible ($0 < -4$ is false). Choice C is incorrect because "or" would cover the entire plane (except the lines). Choice D is incorrect because it describes the region above the top line and below the bottom line (empty set).