a. つたえ b. つたわり
The intended meaning is: “The message that I would be late didn’t get conveyed” so you need to choose an intransitive verb, which is b. つたわり.
If you use a. つたえ (and change が to を), it means you (or somebody specified in the context) didn’t intentionally convey the message.
This question was taken from EasyJapaneseE’s“Transitive verbs vs Intransitive verbs” module. If you need to revise the Transitive verbs vs Intransitive verbs, this module will give you plenty of practice. For details, click the relevant link below.