What Does the Lyric, "If a Body Catch a Body

What does the lyric, "if a body catch a body coming through the rye" that Holden misquotes make him imagine?

A) Walking in the street just along the curb while cars race by, honking
B) Standing at the edge of a cliff and catching children who come too close.
C) Being a little kid playing in the Rye
D) Running off to become a farmer in Maine or Vermont.