Answer:
A. Editing because Clark is going over his draft for typos and errors for spelling and grammar.
Step-by-step explanation:
It can be B because publishing is when your finished and you show it to the world. D would be wrong because revising is when you finish it but you find something incorrect and go in to fix it. C is just writing the essay in general, it may be going back and writing more. So that's why I would say A editing.