Step 1: This is a factual question asking to identify the author of the poem "Koel".
Step 2: The poem "Koel" uses the image of the Indian cuckoo to express intense longing and passion.
Step 3: The poem was written by the Punjabi poet and scientist, Puran Singh. The marked answer (A) is incorrect; Laxmi Prasad Devkota wrote "The Sleeping Porter."