Sentences of a paragraph are given below in jumbled order. Arrange the sentences in the correct order to form a meaningful and coherent paragraph.
A. A small stream emerged from a cluster of rocks to feed the pool.
B. It was on such a day - a hot, tired day - that Ranji found the pool in the forest.
C. During the monsoon, this stream would be a gushing torrent, cascading down from the hills, but during the summer, it was barely a trickle.
D. The water had a gentle translucency, and you could see the smooth round pebbles at the bottom of the pool.

Let's find the logical sequence of the sentences:
Sentence B introduces the main subject—Ranji finding a pool in the forest on a hot, tired day. This serves as an excellent opening sentence.

Sentence D describes the quality of the water in the pool that Ranji just found ("The water had a gentle translucency...").

Sentence A explains where the water in the pool came from ("A small stream emerged from a cluster of rocks to feed the pool").

Sentence C expands upon the behavior of "this stream" mentioned in sentence A during different seasons (monsoon vs. summer). Hence, C must immediately follow A.

Combining these, the coherent arrangement is B-D-A-C.