1 - Perform the following rest...
2 - Storag the mictosoft...
3 - Store the file in a blode storage container.

Office UI Fabric is Microsoft's official front end framework for building User Interface experiences for Office and Office 365. In simple terms it gives you the look and feel for your component. Moreover, they are open source, mobile responsive and reusable, no need to create from scratch just refer them in your code and start utilizing them.
Microsoft modern SharePoint out of the box webparts are made up these Office UI Fabric framework, so to maintain consistency look and feel as like Office it's better to use these components in our custom SPFx webparts.
Incorrect Answers:
D: At Build 2019 [November 2019], Microsoft announced Fluid Framework, a new technology and set of experiences that will make collaboration seamless by breaking down the barriers between apps. It offers three key capabilities. First, experiences powered by the Fluid Framework will support multi-person coauthoring on web and document content at industry-leading speed and scale. Second, it provides a componentized document model that allows authors to deconstruct content into collaborative building blocks, use them across applications, and combine them in a new, more flexible kind of document. Third, the Fluid Framework makes room for intelligent agents to work alongside humans to translate text, fetch content, suggest edits, perform compliance checks, and more.

MSGraphClient is a new HTTP client introduced in SharePoint Framework v1.6.0 that simplifies connecting to the Microsoft Graph inside SharePoint Framework solutions.
With MS Graph we use MSGraphClient to get information about the current user; this.context.msGraphClientFactory
.getClient()
.then((client: MSGraphClient): void => {
// get information about the current user from the Microsoft Graph
client
.api('/me')
.get((error, response: any, rawResponse?: any) => {
// handle the response
});
});
Reference:
https://www.c-sharpcorner.com/article/show-outlook-messages-from-microsoft-graph-in-spfx-client-side-web-part/

Explanation
Graphical user interface, text, application, email Description automatically generated