Question

Match List-I with List-II.

List-I	List-II
(A) Close contour lines	(I) Foot hill
(B) Wider contour lines	(II) Higher contour values outside
(C) Depression	(III) At right angles
(D) Crossing of ridge lines	(IV) Top of hill

Choose the correct answer from the options given below:

• (A) - (IV), (B) - (I), (C) - (II), (D) - (III)
• (A) - (I), (B) - (II), (C) - (III), (D) - (IV)
• (A) - (II), (B) - (III), (C) - (I), (D) - (IV)
• (A) - (IV), (B) - (II), (C) - (I), (D) - (III)

Hint:

Think about what close versus wide contour spacing tells you about slope, and what a closed loop with rising values around it represents.

Answer 1

The Correct Option is A

A quicker way to solve this match-the-following is to fix the pairs you are most sure of first and then eliminate wrong options.

The safest fact in surveying is that contours always cross a ridge or a valley line at a right angle, since the direction of steepest slope (the ridge/valley line) is always perpendicular to the lines of constant elevation (the contours). So (D) must go with (III). Checking the four options, only option 1 and option 4 keep (D) - (III); options 2 and 3 can be dropped right away.

Next, look at depression. A depression is a closed contour loop, and by convention the innermost contour of a depression carries the lowest value, so elevation values increase as you move away from the centre, that is, higher contour values lie outside the loop. So (C) must go with (II), not with (I) or with the foot hill idea. Between the two remaining options, option 1 pairs (C) - (II), while option 4 wrongly pairs (C) with (I) (foot hill). This rules out option 4.

That leaves option 1 as the only surviving choice, giving (A) - (IV), (B) - (I), (C) - (II), (D) - (III). This also matches the general slope rule: closely packed contours near the summit (top of hill) and widely spaced contours near the base (foot hill).

\[\boxed{\text{Option 1: (A)-(IV), (B)-(I), (C)-(II), (D)-(III)}}\]