Does Dynamic DB support in-place atomic updates?

A.
It is not defined

B.
No

C.
Yes

D.
It does support in-place non-atomic updates

Explanation:
Q: Does DynamoDB support in-place atomic updates?
Amazon DynamoDB supports fast in-place updates. You can increment or decrement a
numeric attribute in a row using a single API call. Similarly, you can atomically add or remove
to sets, lists, or maps.
https://aws.amazon.com/dynamodb/faqs/