Sentences (A), (B), and (C) are grammatically incorrect.
(A) should be “He has been sleeping for two hours.”
(B) should be “We went to the movies last night.”
(C) should be “I saw him yesterday.”
(D) is correct as it follows subject–verb agreement.
Natural numbers and Integers are not equinumerous since
$\mathbb{Z}$ (integers) is a proper superset of $\mathbb{N}$ (naturals).
All other statements are true.
Solution:
Sentence is in **past tense** (“Did you think”),
so the action that happened **before** that must be in **past perfect tense**.
Correct form: “Did you think you **had seen** me somewhere before?”