**Core Concept**
Determining protein structure is a crucial aspect of biochemistry and molecular biology, as it helps understand the function and interactions of proteins. Protein structure can be determined using various biophysical and biochemical methods.

**Why the Correct Answer is Right**
The correct answer involves X-ray crystallography, which is a widely used method to determine the three-dimensional structure of proteins. This technique involves bombarding a crystal of the protein with X-rays and measuring the diffraction pattern produced. The diffraction pattern is then used to reconstruct the three-dimensional structure of the protein. Other methods include NMR (Nuclear Magnetic Resonance) spectroscopy, which is used to determine the structure of smaller proteins or protein complexes, and mass spectrometry, which is used to determine the sequence and structure of proteins.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect as it does not specify any particular method for determining protein structure.
* **Option B:** This option is incorrect as it is a technique used for DNA sequencing, not protein structure determination.
* **Option C:** This option is incorrect as it is a method used for determining the function of proteins, not their structure.

**Clinical Pearl / High-Yield Fact**
A key point to remember is that understanding protein structure is crucial for understanding protein function, and vice versa. Many diseases, including genetic disorders and cancer, are caused by mutations in protein structure, which can disrupt protein function.

**Correct Answer: B. X-ray crystallography, NMR spectroscopy, and mass spectrometry**