Guest mode causes certain settings to be hidden.

chrome/browser/resources/options/browser_options.css

 /* Copyright (c) 2012 The Chromium Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file. */
 
 #change-home-page-section {
   margin-left: 30px;
 }
 
 #home-page-url {
   display: inline-block;
@@ skipping 434 matching lines @@
 
 #accessibility-autoclick .controlled-setting-with-label {
   -webkit-box-align: baseline;
 }
 
 #accessibility-autoclick label + select {
   /* Same as .controlled-setting-with-label > input + span. */
   -webkit-margin-start: 0.6em;
 }
 
+div[guestmode=true] #appearance-section,
+div[guestmode=true] #startup-section,
+div[guestmode=true] #searchBox,
+div[guestmode=true] #reset-profile-settings-section {
+  display: none;
+}
+
 footer {
   display: flex;
 }
 
 #version-button {
   -webkit-margin-start: auto;
   color: #999;
 }