Airports for 200
While taxiing on the taxiway centerline you notice there are dashed yellow line on both sides of the taxiway centerline. This taxiway marking indicates that you are approaching what?

Answer
A runway hold short line.

Bonus: These "Enhanced Taxiway Centerline" markings mean that you are within how many feet of the runway hold short line?
Answer to Bonus Question150 feet
Ref: AIM 2-3-4