What is the correct answer?

It is spoken like a word

1.       CIA is an example of:

Should abbreviations of the days of the week be written with a capital initial letter?

Should abbreviations of the time (hour, minute) be written with a capital initial letter?

a.m. and p.m. are examples of:

Are all of the following words acronyms?

They visited my family the last yr. Was an abbreviation or acronym used in the sentence above?

  It is a shortened version of a written word or phrase used to replace the original?