Which of the following pairs of land forms are surface features of a karst region? i.Clint ii.Grikes iii.Stalagmite iv.Cavin

Analyze the question: We need the pair of features that appear on the surface of a karst (limestone) region, not underground.

Concept: Karst landscapes form where limestone is dissolved by slightly acidic rainwater (carbonation).

• Surface features: limestone pavements made up of clints (the flat-topped blocks) and grikes (the deep fissures between them), as well as swallow holes (sinkholes), dolines, and uvalas.
• Underground features: caves/caverns, stalactites (hang from the roof), stalagmites (grow up from the floor), and pillars/columns.

Going through the options:

• i. Clint: surface feature ✔
• ii. Grikes: surface feature ✔
• iii. Stalagmite: formed inside caves, so it is underground ✘
• iv. "Cavin": this is most likely a misprint of "cavern", which is also underground ✘

So the two surface features are clints and grikes, which together form limestone pavement.

Matching with the options:

• A. i and ii only ✔
• B. i and iii: stalagmite is underground ✘
• C. ii and iii: same problem ✘
• D. ii and iv: cavern is underground ✘

Tip: Remember "Clints and Grikes are on the Ground surface" while "Stalagmites Stand in caves below." Surface = clints, grikes, swallow holes; underground = stalactites, stalagmites, caverns.