Which of the following groups of rivers fall in the Bay of Bengal?

Answer: Option A

The correct answer is A: Ganga, Brahmaputra, Hooghly.
Let's break down why:

The Bay of Bengal is a large bay in the northeastern part of the Indian Ocean.
Rivers that flow eastward through India and Bangladesh generally drain into it.

* Option A: Ganga, Brahmaputra, Hooghly - All three of these rivers eventually flow into the Bay of Bengal either directly or through distributaries.

* Option B: Ganga, Yamuna, Godavari - While Ganga and Godavari eventually drain into the Bay of Bengal, the Yamuna is a major tributary of the Ganga, meaning it flows into the Ganga and then finally to the Bay of Bengal.

* Option C: Ganga, Yamuna, Brahmaputra - Again, Yamuna is a tributary of the Ganga, similar to option B.

* Option D: Ganga, Yamuna, Gandak - The Yamuna and Gandak are tributaries of the Ganga.

So, the only group where all rivers mentioned (Ganga, Brahmaputra, and Hooghly) eventually drain into the Bay of Bengal is Option A.