A Certain Electromagnetic Field Traveling in Vacuum Has a Maximum $1200 \mathrm {~V} / \mathrm { m }$

A certain electromagnetic field traveling in vacuum has a maximum electric field of $1200 \mathrm {~V} / \mathrm { m }$ . What is the maximum magnetic field of this wave? $\left( c = 3.0 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s } \right)$

A) $9.6 \times 10 ^ { - 6 } \mathrm {~T}$
B) $8.7 \times 10 ^ { - 6 } \mathrm {~T}$
C) $2.2 \times 10 ^ { - 5 } \mathrm {~T}$
D) $3.4 \times 10 ^ { - 4 } \mathrm {~T}$
E) $4.0 \times 10 ^ { - 6 } \mathrm {~T}$