Question

while all of the cells in an individual are derived from a single cell, they can differentiate to take on many different types of structure and function. cells can become specialized because
mutations can alter the molecular structure of cell membranes
each cell expresses a different combination of genes
scientists have discovered how to alter the dna sequences of humans
different cells utilize various forms of rna nucleotides

Explanation:

Cell specialization occurs because each cell expresses a different combination of genes. Gene expression regulation determines cell - specific functions and structures. Mutations altering cell membrane structure (not the main reason for specialization), scientists altering DNA sequences (not the natural cause of cell specialization in an individual), and different RNA nucleotides utilization (not the core reason for cell specialization) are less relevant.

Answer:

each cell expresses a different combination of genes