What is one of the features of the standard outline form?

The standard online form always consists of the introduction, at least three or more topic, paragraphs and a conclusion.

Explanation:

Introduction

1. Topic paragraph

2.Topic paragraph

3.Topic paragraph

Conclusions

You can write a thesis statement ( a sentence of what you are writing about ) for the introduction and expand on it for the summary when you have completed the topic paragraphs. You will tell the reader what you are going to tell them in the introduction, tell them in the topic paragraphs and tell them what you told them in the conclusion which may involve a call to action

a.) it provides a clue to solve the mystery.

what are your options ?

i would say years or cherry blossoms