Gabriella Was Looking for Shelter from the Sudden Cloudburst, and at First

Gabriella was looking for shelter from the sudden cloudburst, and at first she had difficulty judging whether the old barn or the farmhouse was closer. However, when she noticed that the barn partially obscured the corner of the house she headed for the barn. Which depth cue did Gabriella use?

A) linear perspective
B) texture gradient
C) relative size
D) interposition