A major investment bank's adjustment of interest rates on mortgages he

(A) adjustment of interest rates on mortgages held by individuals is both a recognition of the depth of the financial crisis and an attempt to balance its books
"a recognition" and "an attempt" are parallel. Hence correct

(B) adjustment of interest rates on mortgages held by individuals both recognize the depth of the finance crisis and attempt to balance their books
Both recognize is awkward and doesn't make sense.

(C) adjustment of interest rates on mortgages held by individuals is a recognition both of the depth of the financial crisis as well as an attempt to balance its books
Change in meaning as both depth and attempt appear to be recognition whereas in A recognition is only for depth.

(D) adjusting interest rates on mortgages to individuals is a recognition both of the depth of the financial crisis and an attempt to balance its books
Same as C

(E) adjusting interest rates on mortgages held by individuals both recognize the depth of the financial crisis and an attempt to balance its books
Same as B

Hence A is correct answer.