Short Answer
Low-coherence interferometry to resolve depth in tissue is the best answer.
Wave and optics questions test how frequency, wavelength, phase, interference, and geometry fit together. Start with the physical picture before choosing the equation.
OCT uses broadband low-coherence light in a Michelson interferometer; the short coherence length provides micron-scale depth resolution in biological tissues.
Why This Answer Is Correct
This is a Hard-level question in Waves & Optics. The prompt is really testing whether you can connect the concept to its defining physical relationship instead of picking a nearby-but-wrong term.
If a waves question feels messy, sketch the geometry or phase relationship first, then return to the algebra.
Choices At A Glance
- A. X-ray absorption contrast
- B. Low-coherence interferometry to resolve depth in tissue
- C. Fluorescence lifetime imaging
- D. Raman spectroscopy
When similar options appear on an exam, eliminate the ones that break the core law, use the wrong units, or confuse a definition with a consequence.
Topic Snapshot
Topic: Waves & Optics
Difficulty: Hard
Best next move: Re-state the governing law in your own words, then solve one more example from the same topic before moving on.