What D yard tracks have third rail?

What D yard tracks have third rail?

• A. 1A-5A
• B. 1D-3D
• C. 2D-4D
• D. 1D-5D

Answer: (D)

Identifying which tracks in a yard are powered by a third rail is the key idea here. For the D yard, the tracks that have third rail run from 1D through 5D, inclusive. So the range 1D through 5D is the correct one because it includes every D-yard track that receives third-rail power. Ranges that end early, like 1D through 3D or 2D through 4D, omit some energized tracks, and a range referring to a different yard (such as A yard) wouldn’t describe the D yard at all.

Identifying which tracks in a yard are powered by a third rail is the key idea here. For the D yard, the tracks that have third rail run from 1D through 5D, inclusive. So the range 1D through 5D is the correct one because it includes every D-yard track that receives third-rail power. Ranges that end early, like 1D through 3D or 2D through 4D, omit some energized tracks, and a range referring to a different yard (such as A yard) wouldn’t describe the D yard at all.