To write an effective ending to your essay, you should
a. ask the reader to take some kind of action.
b. relate a humorous anecdote.
c. write out a formal summary of your overall message.
d. end on a note that's likely to stick in the reader's mind.

The given choices are all relevant to what is asked. They can all be used depending on the type of essay you are crafting. If you are writing a humorous message, a humorous anecdote as an ending can be effective. If you’re writing a formal, informative essay, a formal summary of your overall message would make sense. If you are promoting your own ideals and beliefs, you can either ask the reader to take some kind of action or end on a note that's likely to stick in the reader's mind. There is no definite answer here since it would largely depend on your essay type. 

Is the letter a i thin i hope it

What’s the choices