update: interaction images and scrolling content (#1282)

Co-authored-by: Lauren Rice <[email protected]>

src/pages/components/dropdown/usage.mdx

@@ -303,12 +303,12 @@ Carbon has one layer style called a `box-shadow`. The box-shadow is placed behin
 
 ### Scrolling behavior
 
-Scroll bars may not always be enabled so we recommend showing 50% of the last option's container height to indicate there is more to see within the menu. We recommend starting a scroll at the fifth option in the menu list, but this may vary based on your specific use case.
+Scroll bars may not always be enabled so we recommend showing 50% of the last option's container height to indicate there is more to see within the menu. We recommend starting a scroll at the sixth option in the menu list, but this may vary based on your specific use case.
 
 <Row>
 <Column colLg={8}>
 
-![Dropdown scrolling menu option cutoff.](images/dropdown-usage-7.png)
+![Dropdown scrolling menu option cutoff.](images/dropdown-usage-7a.png)
 
 </Column>
 </Row>