What do events in a transaction have in common?

What do events in a transaction have in common?
A . All events in a transaction must have the same timestamp.
B . All events in a transaction must have the same source type.
C . All events in a transaction must have the exact same set of fields.
D . All events in a transaction must be related by one or more fields.

Answer: B

Explanation:

Reference: https://docs.splunk.com/Documentation/Splunk/8.0.3/Knowledge/Abouttransactions