Task: songer_source

What follows is an opinion from a United States Court of Appeals. Your task is to identify the forum that heard this case immediately before the case came to the court of appeals.

PER CURIAM.
Appellant sought release by habeas corpus from confinement under two consecutive sentences he is serving in the Federal Penitentiary at Leavenworth, Kansas. He contends that the prison authorities erred in aggregating his two sentences for the purpose of computing good time allowance and that if the sentences are separately considered for that purpose, as he contends they must he considered, he has served his time on both sentences and is entitled to release. He has appealed from a judgment denying him his release.
We have consistently held that separate sentences are considered as a single sentence, consisting of the aggregate of such sentences, for . the purpose of computing good time allowance.
It is conceded that if the two sentences appellant is serving are aggregated and considered as a single sentence for the computation of good time allowance, as they must be, he is not now entitled to release. Since that is so, this action is premature.
The judgment appealed from is, therefore, affirmed.
. Grant v. Hunter, 10 Cir., 166 F.2d 673; Mills v. Aderbold, 10 Cir., 110 F.2d 765.

Question: What forum heard this case immediately before the case came to the court of appeals?
A. Federal district court (single judge)
B. 3 judge district court
C. State court
D. Bankruptcy court, referee in bankruptcy, special master
E. Federal magistrate
F. Federal administrative agency
G. Court of Customs & Patent Appeals
H. Court of Claims
I. Court of Military Appeals
J. Tax Court or Tax Board
K. Administrative law judge
L. U.S. Supreme Court (remand)
M. Special DC court (not the US District Court for DC)
N. Earlier appeals court panel
O. Other
P. Not ascertained
Answer:

Answer: A