For Immunoglobulin Heavy and Light Chain Genes, and for T-Cell $\beta$

Multiple Choice

For immunoglobulin heavy and light chain genes, and for T-cell receptor $\beta$ chain genes, there are a large number of V gene segments, and relatively few J and/or D segments that rearrange to form the final coding sequence for each gene. The TCR $\alpha$ locus is different in this regard, and this difference is thought to reflect the fact that nearly all $\alpha$ : $\beta$ T-cell receptors recognize a peptide bound to an MHC molecule. This unique feature of the T-cell receptor $\alpha$ locus is:

A) The presence of only five different V $\alpha$ gene segments
B) The presence of two different C $\alpha$ coding sequences
C) The presence of over sixty different J $\alpha$ gene segments
D) The absence of D gene segments
E) The large sequence distance separating the V $\alpha$ gene segments from the J $\alpha$ gene segments