Question

Arrange the following sediments in ascending order of their size. \[ \begin{aligned} A.&\ \text{Pebble} B.&\ \text{Boulder} C.&\ \text{Granule} D.&\ \text{Cobble} \end{aligned} \] Choose the correct answer from the options given below:

• A. A, C, D, B
• B. C, D, A, B
• C. A, D, C, B
• D. C, A, D, B

Hint:

Standard sediment size sequence: \[ \boxed{ \begin{aligned} \text{Granule} &< \text{Pebble} < \text{Cobble} < \text{Boulder} \end{aligned} } \] Mnemonic: “GPCB = Granule, Pebble, Cobble, Boulder.”

Answer 1

The Correct Option is D

Concept: According to the Udden--Wentworth grain-size classification, sediments increase in size from granules to pebbles, cobbles, and finally boulders.

Step 1: Recall the standard grain-size sequence. \[ \boxed{ \text{Granule} \;<\; \text{Pebble} \;<\; \text{Cobble} \;<\; \text{Boulder} } \]

Step 2: Replace with the given letters. \[ \boxed{ C \rightarrow A \rightarrow D \rightarrow B } \] Hence, \[ \boxed{\text{(D)}} \]