What is the position effect in relation to gene expression?

• A. The position effect is the result of a gene's sequence being mutated.
• B. The position effect refers to the influence of a gene's location near heterochromatin on its expression level.
• C. The position effect is the result of a gene being transcribed into RNA.
• D. The position effect is the influence of a gene's proximity to the cell membrane.

Answer: (B)