Answer: The best definition of 'deliberation' is consideration.
Explanation: The word 'deliberation' is a noun and it refers to the act of considering something carefully, that is to say it refers to the act of thinking thoroughly before doing or saying something in order to make good decisions. In the sentence provided, "deliberation" is collocating with the adjective "calm", but it can also collocate with other words such as "careful" and "slow".
