Cell line origin check: which established cell line is derived from a mouse embryo (embryo fibroblasts used widely in research)?

Introduction / Context:
Authenticating cell lines and recalling their origins is essential for interpreting experimental results. The NIH 3T3 line is a classic mouse embryo fibroblast line used in transformation assays, growth studies, and transfection optimization.

Given Data / Assumptions:

• 3T3: mouse embryo fibroblasts.
• BHK: baby hamster kidney (hamster origin).
• HeLa: human cervical carcinoma (human origin).
• BTK: not a standard established line acronym in this context; commonly refers to a kinase, not a cell line.
• Vero: African green monkey kidney.

Concept / Approach:
Match each widely known line to its species. Only NIH 3T3 comes from mouse embryo fibroblasts among the options, making it the correct choice for this origin-focused question.

Step-by-Step Solution:

Verification / Alternative check:
Standard cell repositories (for example, ATCC) document the origins: NIH 3T3 (Mus musculus), BHK (Mesocricetus auratus), HeLa (Homo sapiens), Vero (Chlorocebus sabaeus).

Why Other Options Are Wrong:

• B/C/E: Hamster, human, and monkey lines respectively; not mouse embryo fibroblasts.
• D: BTK is not a conventional cell line designation here.

Common Pitfalls:
Confusing 3T3 with 3T3-L1 (a subline used for adipogenesis studies) but both are mouse-derived.

Final Answer:
3T3