Question Mark After a Direct Question
The Question Mark
Rulebase Summary
Use a question mark to end any sentence that directly asks a question. This includes questions beginning with who, what, when, where, why, and how, as well as direct questions embedded within quotations. A speaker's inflection can turn any group of words into a question — the same words can be a statement or a question depending on how they are spoken.
Examples
Q. What time did you arrive at the hospital.
Q. What time did you arrive at the hospital?
Direct question needs a question mark, not a period.
Q. Who gave you permission to enter the building.
Q. Who gave you permission to enter the building?
Questions starting with who/what/when/where/why/how take a question mark.
Transcript Notes
Inflection is everything. The identical words ('This is all.' vs. 'This is all?') take different punctuation depending on how the speaker delivers them. Punctuate as you write — capturing inflection in the moment is more reliable than guessing later.
Style Guide References (2)
Morson's
BGGP