use of semicolon

[karenshushang]

Below is the correction answer choice for a sentence correction question with the entire sentence underlined. I eliminated this choice because I thought it shows the wrong usage of semicolon, which is usually used to join two independent clauses or used in a list. Will you please explain the use of semicolon in this situation? Thank you.

Karen

Correction Answer:
A recent study has found that most eligible American workers fail to make the maximum allowed contribution to their employer-offered retirement plans; among the explanations cited are increasing worker mobility between companies, poor financial planning on the workers' part, and excess complexity in the plans themselves.

[tim]

how exactly is the rule being violated here? these are two independent clauses..