Fluoroquinolones Are Known to Be Effective Against Both Gram-Negative and Gram-Positive

Fluoroquinolones are known to be effective against both gram-negative and gram-positive organisms.How is this possible?

A) Fluoroquinolones that are effective against gram-negative organisms block the enzyme topoisomerase IV,which stops the migration process of the two new strands to opposite sides of the cell.
B) Fluoroquinolones that are effective against gram-positive organisms block the enzyme DNA gyrase,which stops relaxation of the supercoil of the DNA.
C) Fluoroquinolones that are effective against gram-negative organisms block the enzyme DNA gyrase,and those effective against gram-positive organisms block topoisomerase IV.
D) All fluoroquinolones are effective against both gram-negative and gram-positive organisms.There is no difference in the way they block bacterial DNA replication.