$ a)\;45^{\circ}\; from\; north , 2.61 hrs \\ b)\;60^{\circ}\; from\; north , 1.50\; hrs \\ c)\; 80^{\circ}\; from\; north , 2.15 hrs \\ d)\;75^{\circ}\; from \;north , 1.83 hrs $

Let $v_w$=Velocity of wind

The aircraft should fly along $AC$ with a velocity of $v_{aw}=400 km/hr$ so that the resultant is along $AB$

Let $v_{aw}$ makes angle $\alpha$ with $AB$

$\large\frac{AC}{\sin 45}=\frac{BC}{\sin \alpha}$

$\sin \alpha=\large\frac{BC}{AC} $$\sin 45$

$\qquad= \large\frac{200 \sqrt 2}{400} \times \frac{1}{\sqrt 2}=\frac{1}{2}$

Therefore $ \alpha=30^{\circ}$

The piolt should steer in a direction $(45 + \alpha)=75^{\circ}$ from North towards East

Also $\large\frac{v_a}{\sin (180-75)}=\frac{400}{\sin 45}$

$v_a=\large\frac{\cos 15}{\sin 45} $$\times 400 $

$\quad=\large\frac{0.9659}{0.707}$

$\quad= 546.47 km/hr$

Therefore $ t=\large\frac{1000}{546.47}$

$\qquad=1.83\; hr$

Hence d is the correct answer

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