A magnet oscillating in a horizontal plane has a time period of 2 second at a place where the angle of dip is 30o and 3 seconds at another place where the angle of dip is 60o. The ratio of resultant magnetic fields at the two places is [Pb. PET 2001]

• A.            \[\frac{4\sqrt{3}}{7}\]            
• B.            \[\frac{4}{9\sqrt{3}}\]
• C.            \[\frac{9}{4\sqrt{3}}\]            
• D.            \[\frac{9}{\sqrt{3}}\]