The best method for separation and identification of trace levels of high molecular weight biomolecules is:

Correct option is C

Explanation:
LC-MS (Liquid Chromatography–Mass Spectrometry) is the most effective method for:
· Separating complex biomolecules, especially large and thermally unstable compounds.
· Identifying trace amounts of high molecular weight biomolecules such as proteins, peptides, nucleotides, and metabolites.
Why LC-MS?
· Liquid Chromatography (LC) separates molecules based on their chemical interactions (polarity, size, etc.).
· Mass Spectrometry (MS) identifies and quantifies them by measuring their mass-to-charge ratio (m/z) with high sensitivity and precision.
Additional Information:
· GC-MS is used for volatile organic compounds but not suitable for large biomolecules (they degrade under heat).
· HPLC-UV provides only absorbance data, not molecular structure or mass info.
· GPC (Gel Permeation Chromatography) is for molecular weight distribution, not sensitive to trace levels.