[Incomplete question conditions] Official D: cubes per m² not stated

What you will learn

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

Saved full original October 2021 exam text (local copy of CBP-authored PDF): cover instruction; Exam cover reference list: HTSUS edition; Exam category heading before questions 34-35 (exam PDF page 12); Question 35 stem as printed, including the misspelling CLASSIFICIATION (exam PDF page 12; rendered temporarily and viewed); Question 35 choices A–E as printed (exam PDF page 12; rendered temporarily and viewed); Answer key row 35 (key PDF page 2; rendered temporarily and viewed); HTSUS 2020 Chapter 69 Note 1 (page 69-1; rendered temporarily and viewed); HTSUS 2020 Chapter 69 Additional U.S. Note 3 (page 69-1); HTSUS 2020 heading 6907 article description (page 69-4); HTSUS 2020 lead-in to 6907.21–6907.23 tile subheadings (page 69-4); HTSUS 2020 subheading 6907.21 (page 69-4); HTSUS 2020 6907.21.20 (choice B line, page 69-5); HTSUS 2020 6907.21.30 (choice C line, page 69-5); HTSUS 2020 subheading 6907.30 (page 69-10; actual PNG viewed; text checked against Chapter 69 PDF text); HTSUS 2020 6907.30 glazed size lead-in (page 69-10; actual PNG viewed); HTSUS 2020 6907.30.20 — first glazed branch (page 69-10; actual PNG viewed); HTSUS 2020 6907.30.30 — official D line, under Other (page 69-10; actual PNG viewed); HTSUS 2020 6907.30.40 — remaining glazed line (page 69-10; actual PNG viewed); HTSUS 2020 heading 6914 and 6914.10.80 (choice E line, page 69-19); HTSUS 2020 6914.10.80 statistical line (page 69-19) · October 21, 2021 Customs Broker License Examination, Category VIII – Classification (question 35 on exam PDF page 12, rendered temporarily and viewed); 'October 2021 Customs Broker License Exam Answer Key', row 35 on key PDF page 2 (rendered temporarily and viewed). Cover reference: HTSUS 2020 Basic Edition, no supplements; Chapter 69 pages 69-1, 69-2, 69-10 and 69-19 viewed as actual images.
Explained using the historical edition for this exam.