[Source or answer dispute] Official D: wild yak listed endangered

What you will learn

Disputed-question explanation: official result first, then historical evidence, limitations and uncertainty.

Saved full original April 2023 exam and key text: question 42 stem as printed; Same file; options A–E as printed; Same file; official key heading; Same file; official key row 42 text; Same file; exam cover CFR reference (no Title 50 reference listed); Same file; exam cover instruction; Same file; 'Category VII – Partner Government Agencies (PGA)' heading on page 19 directly above question 42; Local copy of CBP-authored exam and key PDF (not a live CBP URL); its page 19 was rendered temporarily outside the repository (pdftoppm, 110 dpi, /tmp) and the actual page image viewed: Category VII heading, question 42 with 'NOT' in bold, all options A–E, and question 43; no saved page-19 PNG exists in source-evidence and none was added; Actual official key page image viewed; row 42 'Answer D' with citation '19 CFR 12.26'; no reason printed; 2021 19 CFR 12.26(a)(1)(iv), (vi), (viii), (x) — named live specimens (GovInfo 2021 annual edition, text); Same file; 12.26(a)(1)(vi); Same file; 12.26(a)(1)(viii); Same file; 12.26(a)(1)(x); Same file; 12.26(a)(1) closing — prohibition except under FWS Director permit; Same file; 12.26(a)(1) endangered-list sentence; Same file; 12.26(a)(4) federal-agency own-use exemption (not stated in the stem); Same file; 12.26(b) lead-in and (b)(3) wild ruminants; 2021 GovInfo XML of 19 CFR 12.26 (DATE 2021-04-01); header confirms edition; Saved 2021 Part 12 PDF text (19 CFR Ch. I (4–1–21 Edition)); 12.26(a)(1) endangered-list sentence and (b)(3) cross-checked; Same file; 12.26(b)(3) opening as printed; Saved official annual 2021 50 CFR 17.11 PDF text (50 CFR Ch. I (10–1–21 Edition)); mammals table entry for wild yak; Same file; 17.11(e) Status column key; Same file; page header edition line; Local copy of official GovInfo 2021 Title 50 vol 2 § 17.11 PDF (not refetched); Actual 2021 50 CFR 17.11 table page image viewed (PDF page 13, printed page 23, header 'U.S. Fish and Wildlife Serv., Interior § 17.11'): row 'Yak, wild | Bos mutus (=grunniens m.) | Wherever found ... | E | 35 FR 8491, 6/2/1970.' · April 26, 2023 Customs Broker License Examination, question 42 on PDF page 19 under 'Category VII – Partner Government Agencies (PGA)' (page 19 rendered temporarily from Apr2023-original-resume0102.pdf and viewed); 'APRIL 2023 CUSTOMS BROKER LICENSE EXAM ANSWER KEY', row 42 on key PDF page 36 (Apr2023-key-page36.png). Cover reference used: Title 19, Code of Federal Regulations (2021 Revised as of April 1, 2021); other cover references not used. Text used: complete 2021 19 CFR 12.26 (GovInfo 2021 XML/text, DATE 2021-04-01, cross-checked with the saved 2021 Part 12 PDF text, 4–1–21 Edition). The FWS Endangered Species List that 12.26(a)(1) refers to was read in the official annual 2021 50 CFR 17.11 (10–1–21 Edition; table PDF page 13, printed page 23, PNG viewed); Title 50 is not an exam cover reference and is disclosed as such; the wild yak listing citation is 35 FR 8491, 6/2/1970, before both editions. No ruling, later revision or current law is used.
Explained using the historical edition for this exam.