Correct option is C
Explanation-
Option c - Treatment with 5-bromo-2’-deoxyuridine (BrdU), followed by UV-A exposure
5-bromo-2'-deoxyuridine (BrdU) - A synthetic analog of thymidine. It incorporates into the DNA of actively dividing cells (those in the S-phase).
UV-A Exposure - BrdU makes DNA more photosensitive.
When exposed to UV-A radiation, it causes DNA strand breaks and cell death in those BrdU-labeled cells. This selectively kills only the dividing cells, sparing non-dividing ones.
Incorrect options-
Option a - Exposure to UV radiation at 250 nm
This damages all cells, not just dividing ones. It lacks selectivity for newly dividing cells.
Option b - Treatment with 5-ethynyl-2’-deoxyuridine (EdU), followed by doxorubicin hydrochloride treatment
EdU incorporates into DNA like BrdU, but EdU is used for detection, not killing. Doxorubicin is a general cytotoxic drug — not specific to newly dividing cells unless tightly dosed.
Option d - Thymidine treatment followed by vinblastine treatment
Tritiated thymidine is radioactive and incorporates into DNA, but is more commonly used for labeling, not killing. Vinblastine disrupts mitosis, but again it may not target only S-phase cells unless combined strategically.
So, the correct answer is option c - Treatment with 5-bromo-2’-deoxyuridine (BrdU), followed by UV-A exposure
