60.
Your Answer is
Correct Answer is G
Explanation
According to the meaning of the sentence, the expression "this system is a map for drawing the route below..." is the most suitable for item G subterranean routes "underground routes".
Item F: vicinities creeping beneath "spread in the surrounding area below" is unclear.
Item H: submerged zones "underwater area".
Item J: low-down alleys "very low alley" is wrong.