Show off your theory chops with my weekly challenge! You’ll find a new question here every Monday. Please comment to post your reply.
This week’s challenge:
Here’s the start of a fugue I wrote in my undergraduate years. Is the answer real or tonal?

Reply to post your answer, and check back on Friday, November 19th to see if you’re right!
ANSWER for 11/15/21
This is a TONAL answer to our fugue subject.

A real answer is identical to the fugue subject, note for note, merely transposed to the key of V. But a tonal answer is slightly altered so that its first few notes sound like we’re still in the key of I. The DO–SO leap in the subject (A to E) is reversed to SO–DO in the answer. This makes the transition from subject to answer smoother and less jarring. Tonal answers typically follow fugue subjects that have this explicit leap (DO to SO, or vice versa).
Composers deemed this necessary because the fugue was a musical form that appeared before the rules of common-practice harmony had fully cemented. If you want to modulate from the tonic key to the dominant (I to V), the common-practice method is to use an applied dominant. In this case, you’d write a II7 chord (V of V) and tonicize the new key. But in a fugue, we don’t do this. We have the subject in the key of I, and then BAM––we have the answer in the key of V. So the tonal answer was a kind of workaround, smoothing over the key change.
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Tonal answer
It’s tonal because the answer uses an interval of a perfect fourth between the 4th and 5th pitches (unlike the first statement which uses a P5th). A “real” answer would match all intervals.
Tonal