What is another word for a regular series of actions

Another word to describe regular series of actions is "process".

Process - a series of actions or steps taken in order to achieve a particular end.

Some examples of processes are: manufacturing – a product assembly process, finance – an invoicing process, a risk management process.

i would say b. research typically uses a variety of sources

chronological thinking is an indispensable tool to structure a historical narrative and to give meaning to a sequence of events. the final section presents the results of a survey to test the chronological thinking of lower secondary school students carried out by the educational research institute.