The answers are B and D.

The sentence criticizes Rectangle Record for overproducing their signature line of derivative goods, specifically repackaged old CDs. We are looking for words that accurately convey the idea of an excessive and interfering abundance in the market.

A. dearth: Dearth refers to a scarcity or lack of something. In the context of the sentence, a dearth of repackaged old CDs would suggest a shortage, which doesn't align with the idea that Rectangle Record has overproduced them.
B. glut: Glut refers to an excessively abundant supply of something. In the context of the sentence, a glut of repackaged old CDs accurately captures the notion of overproduction and interference with innovation.
C. deficiency: Deficiency means a lack or shortage. Similar to "dearth," it suggests a scarcity rather than an excess, so it is not the correct answer.
D. surfeit: Surfeit refers to an excessive amount or surplus. This term aligns well with the idea of overproduction and interference with innovation.
E. abundance: Abundance refers to a plentiful supply. While "abundance" itself is not incorrect, the sentence is emphasizing the negative consequences of excessive production, so it is not the most suitable term.
F. profusion: Profusion refers to an abundance or large quantity. Similar to "abundance," it is not incorrect, but it doesn't capture the negative connotation of excess and interference with innovation in the context of the sentence.