Why is moving the brush from the outside toward the inside useful in stencil work?

Correct answer: It reduces the chance of pushing paint under the edge

The governing concept is preventing seepage at a stencil boundary. Moving the brush from the outside toward the inside directs pressure and paint away from the exposed edge, so less pigment is forced beneath the stencil. Using a small amount of moderately thick paint improves control further. Option A is correct; brush direction cannot make paint watery, change stencil transparency, or thicken paper.