What must be in place before you can reattach a sketch to new geometry?

To reattach a sketch to new geometry in NX, it is essential that the geometry has a timestamp that comes before the sketch. This ensures that the sketch is able to reference and relate to the geometry correctly. Without this temporal relationship, the software cannot effectively integrate the sketch back into the design, as the external geometry it references needs to exist prior to the sketch for proper alignment and constraint application.

The other choices focus on different aspects of sketch and geometry interaction, but do not address the core requirement of establishing a chronological order between the geometry and the sketch. Fully constrained geometry, two-dimensional constraints, or the lack of dependencies do not inherently provide the necessary context for reattaching the sketch; what matters is the sequence of creation, which is indicated through timestamps. Thus, having the correct timing in place is a fundamental step in the process.