The Accordion component is the most appropriate choice for organizing a large number of fields into manageable sections on a Lightning record page. It functions as a container that can hold other components, such as Field Sections (when using Dynamic Forms), and presents them as a series of collapsible vertical sections. This directly addresses the requirement to break up the user interface, making it easier for users to navigate and find information among the 100+ fields without excessive scrolling.

A. Highlights panel: This component is designed to display a summary of key fields at the top of a record page, not to organize the main body of fields.

B. Record detail: This component displays all fields and sections from a traditional page layout in a single, non-tabbed block, which would not solve the organizational problem.

C. Field section: This is a component available within Dynamic Forms used to group fields, but it must be placed inside a container like the Accordion or Tabs component to create a sectioned layout.

1. Salesforce Help Documentation, "Standard Lightning Page Components":

Accordion Component: "Use the Accordion component to organize your components into collapsible sections." This directly aligns with the requirement to break up fields into separate sections.

Highlights Panel Component: "The highlights panel shows key fields from an object’s page layout... The fields in the highlights panel come from the compact layout assigned to the object." This confirms its purpose is for summarization, not detailed organization.

Record Detail Component: "The Record Detail component displays fields and sections from the page layout associated with the object." This confirms it displays fields but does not inherently provide a tabbed or accordion structure.

2. Salesforce Help Documentation, "Dynamic Forms Overview":

Section: "What Are Dynamic Forms?": "Dynamic Forms is the next step in the evolution of Lightning record pages. It adds the ability to configure record detail fields and sections inside the Lightning App Builder." This documentation clarifies that Field Sections are elements to be placed on the page, often within container components like Accordion or Tabs to achieve the desired layout.