Classic riddle: What is at the very end of the word "rainbow"?

Introduction / Context:
This is a classic English wordplay riddle. At first, it sounds like a question about weather or physics, because rainbows are natural phenomena in the sky. However, the riddle actually refers to the written word "rainbow" and expects you to pay attention to spelling rather than to real rainbows. This type of question appears frequently in reasoning tests to check whether you can recognise when a problem is about language instead of about real world objects.

Given Data / Assumptions:

• The riddle asks: What is at the end of a rainbow?
• There is no mention of science, optics or geography in the wording.
• Options include objects such as a pot of gold and the horizon, as well as the letter W.
• We are allowed to treat "rainbow" as a word, not only as a physical arc of colours.

Concept / Approach:
Many traditional riddles rely on ambiguity. The phrase "at the end of a rainbow" can mean the physical end of a rainbow in the sky or the last character of the written word "rainbow". In storybooks, people sometimes say there is a pot of gold at the end of a rainbow, but that is clearly a myth, not a factual answer. The logical approach is to suspect wordplay and check the spelling. The final letter of the English word "rainbow" is W, so the riddle cleverly points to a single letter, not to a location in the sky.

Step-by-Step Solution:
Step 1: Write down the word "rainbow". Step 2: Look at its letters: r, a, i, n, b, o, w. Step 3: Identify the last letter in the sequence, which is W. Step 4: Compare this observation with the answer choices. Step 5: Recognise that "The letter W" is the only option that directly matches something undeniably at the end of the word "rainbow". Step 6: Conclude that the riddle is about spelling, not about a physical pot of gold or the horizon.

Verification / Alternative check:
A quick verification method is to check whether any option describes something that is always and unavoidably present at the end of any rainbow. In reality, rainbows are optical illusions that do not have a fixed physical end where you can place an object. However, the letter W is always at the end of the written word "rainbow". This makes the letter choice stable and reliable, while options like pot of gold or horizon are based on stories or variable locations.

Why Other Options Are Wrong:
Option A, the pot of gold, comes from folklore but has no basis in real physics or in the wording of the riddle.

Option B, the horizon, is not specific to rainbows and changes with the observer's position, so it is not a fixed "end".

Option D, sunlight, is what creates a rainbow but is not "at the end" of it in any strict sense.

Option E, raindrops, are spread throughout the region where the rainbow is seen, not only at its end.

Common Pitfalls:
Many learners fall for storybook images of a pot of gold or try to imagine where a rainbow physically touches the ground. This leads them away from the actual trick of the question, which is about spelling. Whenever a riddle sounds impossible or relies on mythology, it is a good idea to check whether it might be talking about a word, a letter or a sound instead.

Final Answer:
At the end of the word "rainbow" you find the letter W.